Two weeks ago, on the 9th of August, we celebrated our Golden Jubilee with a parade at the Padang. For everyone who took part at the Padang, at the Floating Platform, around the Bay, watching at home or overseas, that night was something special to remember. It was not just a birthday bash, we were celebrating something far greater.

First of all, we celebrated our resolve to defend ourselves and to survive over the last 50 years. We started out at Independence with only two infantry battalions in a rough neighbourhood. But our pioneers were determined to defend ourselves - we built up the Singapore Armed Forces (SAF). Within four years, we paraded a few of our units on National Day in 1969. Overhead, we had one Hunter aircraft and one Alouette helicopter flying the Singapore flag. In the mobile column, we had 18 AMX-13 tanks, which were appearing in public for the first time and Major Goh Lye Choon was a second-in-command. Singaporeans cheered, everyone understood what it meant and it was not just Singaporeans who took note.

Fifty years later, our pioneer servicemen kicked off the SG50 vintage Parade.

Above us, instead of one Hunter fighter, we had 20 F-16s, flying across the Padang forming the number 50. A Chinook helicopter flew the flag, escorted by two Apaches and Colonel Goh Lye Choon, now retired, was once against the second-in-command of the mobile column, this time on a Leopard tank. That is him.

Behind Lye Choon, 178 vehicles rolled past the City Hall steps. Tanks, artillery, AA missile launchers, special ops vehicles, Hazmat vehicles and completing the mobile column we had nine vehicles carrying nine families.

They were the pioneers who had served in the SAF and the Home Team and they were on parade with their children who are presently serving and, in two cases, with their grandchildren too.

Secondly, on National Day, we celebrated how we had turned vulnerability into strength. We started off with no hinterland and a weak economy. We depended on our entrepot trade, but our neighbours were building their own ports and sought to bypass us. Our workers were unskilled and anxious about their future but we determined to make the world our hinterland. And the tripartite partners worked together, worked hard to create the best workforce in the world. The Government, the employers and the unions, we worked together. Business Environment Risk Intelligence (Beri) every year ranked us No. 1 in the world. And with that workforce, we made PSA and Changi the best in the world.

We were a poor Third World country; people lived in cramped and squalid slums, no modern sanitation, no utilities, but we built HDB flats to house all of us and made Singapore a First World metropolis and our beautiful home.

Nearly all our water came from Johor and every now and again, when an issue arose with Malaysia, some crazy politicians would threaten to turn off the tap, to get us in line - but we did not die of thirst. We cleaned up our rivers, we dammed them up to become reservoirs, we built Marina Barrage and turned Marina Bay into Marina Reservoir. Our whole island became a catchment area. We invented Newater and on National Day 2002, we toasted our success, "Huat Ah!"

Thirdly, we celebrated our journey from Third World to First as one united people. When we separated from Malaysia, we were not yet one people, memories of the race riots were fresh and raw. The minorities were uncertain of their place in the new country. They saw what had happened in Malaysia, they wondered, will the new Singapore Government keep its promise of a multiracial society? But 50 years on, we celebrate as one united people. On National Day, when the siren sounded, we stood and recited the Pledge together - regardless of race, language or religion. We sang Majulah Singapura.

WHAT GOT US TO SG50

What an exhilarating journey these 50 years have been. How did we get here? I will put it down to three factors. Firstly, we determined to be a multiracial society. Secondly, we created a culture, a culture of self-reliance and also mutual support. And thirdly, we kept faith between the Government and the people.

• Multiracialism

First of all, multiracialism. We separated from Malaysia because we believed in this ideal of a multiracial society. We believed that before race, language and religion, we should first and foremost be Singaporean. That was the fundamental reason for our foundation as a country. So we came down hard on chauvinists and racial extremists. We built HDB estates where all the different races lived and mingled together. There are no segregated ghettos in Singapore. We made English our working language and gradually all our schools shifted to teaching in English. We created group representation constituencies (GRCs) so that minorities would always be represented in Parliament and, this way, we encouraged all the communities to come together and yet gave each community space to maintain their own cultures and their own ways of life. When delicate and awkward issues arose, we dealt with them together.

For example, when we discovered the Jemaah Islamiah group planning to set off suicide bombs in Singapore after 9/11, we handled it as one people; we did not divide into Muslims and non-Muslims.

At the same time, we made the effort to bring everybody together and to ensure that every community could hold its own and not be left behind. So we set up self-help groups, the communities did, starting with the Council for the Development of Singapore Malay/Muslim Community (Mendaki), later the Singapore Indian Development Association (Sinda), then Chinese Development Assistance Council (CDAC) and the Association of Muslim Professionals (AMP) and the Eurasian Association. The Government supported them and so we progressed together.

Therefore, for SG50, every community in Singapore is celebrating because every community has progressed with the nation. And each group is celebrating with the other groups because we are one united people.

I have attended many SG50 celebrations this year, a Catholic Jubilee Mass at the Indoor Stadium, the SG50 Kita National Day Observance Ceremony here in this campus, led by the Malay/Muslim organisations but with other groups participating, a Buddhist celebration at the Indoor Stadium, a Protestant prayer event at the National Stadium, a joint concert organised by the Taoist Federation, the New Creation Church and others at the Star Performing Arts Centre.

Here you see one of the items - a Chinese gongfu group performing with the silat group. One function.

At one dinner, I had sitting around my table representatives of all the world's major religions and I posted the picture on Facebook. It showed the Rabbi of Singapore together with the Mufti of Singapore and Mr Gurmit Singh, a Sikh leader who was then chairing the IRO, the Inter-Religious Organisation. Each had different dietary rules, each was served food that met his religious requirements, but nothing stopped them from having a meal together and being friends together. In fact, they took a selfie together, which I also posted on Facebook.

Only in Singapore!

Some people may think that racial and religious harmony is not a problem any more and that I am making too much about this. But they would be wrong. Race and religion are always sensitive matters, especially for us, and, in some ways, today, more complex and difficult to handle than 20 years ago, because religiosity has gone up.

Many societies, people are taking their religion more seriously, happens in developed countries like US, Britain, Australia, Germany where you see racial and religious tensions. Happens in Singapore too, not tensions but people taking religion more seriously and everywhere people exposed and vulnerable to extremist ideologies, like the jihadist ideology of ISIS. We are a multiracial and multi-religious society and we are always at risk of deep fault lines opening up and we must never take our present happy state of affairs for granted.

• Self-reliance and mutual support

The second factor of our success, after multiracialism, is our culture of self-reliance and mutual support. We knew right from the start that to strike out and blaze a path on our own, everyone had to pull their weight and be counted, we could not afford free-riders and that is why Mr Lee Kuan Yew exhorted us over and over again to become a rugged society.

We do not use that term quite so often any more, but our people must still be robust and tough, be able to take hard knocks, always striving to be better. No one owes us a living and we have to make our own way forward in the world. But a rugged society does not mean every man for himself. We are strong even though we are small because we are strong together. The ethos of our society is clear: If you work hard, you should do well and that is good for you and we should cheer you and celebrate it, but, at the same time, if you do well, we expect you to help others and everyone has to work together so that we succeed as one Team Singapore.

We have got to inculcate this ethos in our young people too. And that is why we encourage our children to play sports to experience losing and winning together. That is why we send them on adventure learning and character education.

To OBS, Outward Bound Singapore in Pulau Ubin, and also on overseas expeditions, so that they can toughen themselves up and learn to work with one another as a team. When I was in Secondary 4, my principal sent me to OBS - the experience made a deep impression on me.

Nowadays, students have many more opportunities to go for adventure learning, here and also abroad. Tanjong Katong Primary School (TKPS) had a very successful programme, the Omega Challenge. It has been going on for seven years; the students who have been, have testified to how much they benefited from it. Tragically, on their recent expedition to climb Mount Kinabalu, the Omega Challenge group was caught in an earthquake. Seven students, two teachers and a guide died. We all mourned them and grieved with their families, we held a National Day of Remembrance. It will take us a long time to get over this tragedy but life goes on and it is important that we move on. And I know that the other TKPS students and teachers who were on this trip are courageously doing so. We have to go on with the adventure training, we will take the necessary safety precautions but we must keep pushing our limits to bring up a generation who will grow up tough and able to work closely together.

• Trust and good government

The third factor for our success is that we have kept faith between the Government and the people. We have built up this bond between the Government and the people over the past 50 years. The Government has kept its promises, what we said we would do, we did do. We have kept our politics honest, we insisted on high standards of integrity in public life, no corruption, no dishonesty. We are also honest when it comes to policies and when it comes to the choices that we have to make. We do not shy away from hard realities, we do not sugar-coat difficult issues. We do right by Singaporeans. In turn, our people expect the Government to perform, trust the Government to have their interests at heart and support the Government and its decisions to work for the common good. And even in tough times, we can act decisively together.

It was like this with our pioneer generation, for example, on the issue of land acquisition. The Government needed land to build HDB new towns around the island to house our people. To build industrial estates like Jurong to create jobs for our people. Later on to build the MRT network to move people around. So the Government passed laws to acquire land not at the market price, without paying market prices. It was tough for the landowners who suffered financial losses, sometimes more than once. It was tough for the households who had to be resettled, lives were disrupted, thousands, maybe tens of thousands, had to change their livelihoods. But if the Government had not done this, we could not have housed our population and we could not have transformed Singapore, so there were sacrifices but, in the end, it was for the common goal and everybody benefited and I thank all those who sacrificed for this common goal.

Even in recent times, we had to do tough things together. During Sars in 2003, we passed laws urgently on a certificate of urgency to quarantine people at home, to prevent community spread and we will ring you up and ask you to turn up on your camera to show that you are still there. Singaporeans understood this was necessary and they accepted it. Recently, South Korea had a serious outbreak of Mers but they had problems quarantining people. It was not so easy for them to get people to cooperate. There was one case, where a person was missing from her home, they knocked on the door, no answer, telephone no answer, tracked her down via her handphone. She was several hundred kilometres away, playing golf. You can pass the laws but people have to cooperate.

From time to time, new tough issues will come up and we will need your support to deal with them. One tough issue which we already have and which will be with us for a long time to come is immigration and foreigners.

It is a very sensitive matter, not an easy thing to talk about, even at the National Day Rally and Singaporeans understandably have strong views about it. The Government has heard them, we have adjusted our policies, upgraded our infrastructure, slowed down the inflow of foreign workers, tightened up on permanent resident (PR) and citizenship applications, made sure that Singaporeans are fairly treated at work.

But on foreigners and immigration, there are no easy choices. Every option has a cost, has a downside. If we close our doors to foreign workers, our economy will tank. Companies would not have enough workers. Some will close down and our own people working in these companies will lose their jobs. Also we need foreign workers to build our homes and schools, to meet our daily needs, we need foreign domestic help. So we cannot close our doors completely.

On the other hand, if we let in too many foreign workers, our society will come undone. Singaporeans will be crowded out, workplaces will feel foreign, our identity will be diluted and we just cannot digest huge numbers. Therefore, we have got to find something in between, make a right trade-off but, even in between, there is a cost and there is a price and there is a pain.

Companies will still find their costs going up, they will have to pass some of these costs on to consumers. Things would not be as cheap. Companies will have to pass up opportunities too. When they can see the opportunities but cannot get the workers, many companies will not be able to expand. And yet because some foreign workers will still be coming in, there will be Singaporeans who will feel that Singapore is changing too fast and will resent having to compete with non-Singaporeans. Whichever option we choose, it will involve some pain.

But I believe that I am doing what Singapore needs and what best safeguards your interest. If I did not believe that, I would not be doing it. It is my responsibility to make this decision, to make this judgment and then to act on your behalf. And having acted on your behalf, to account to you for the results and for the reasons why I decided the way I did. I think I owe it to you. You have elected me. This is my duty, I cannot shirk it.

CHALLENGES AT SG50

These principles have brought us here - multiracialism, self-reliance and mutual support, keeping faith between the Government and people. These principles have made us special. They are not so easy to do. Easy to say, not so easy to do. Very few countries have got this right but, by and large, we have got it right.

And Singapore has to stay special because if we are just a dull little spot on the map, a smudge, we are going to count for nothing. We have to be a shining red dot. If we are soft and flabby, we are going to be eaten up. We have to be rugged and we have to have that steel in us. If we are divided, whether along racial lines or class lines, we cannot survive. We have to stand as one united people, we have to progress together.

• TOMORROW: Excerpts from PM Lee's speech on the external environment and the need for quality leaders.