On Tuesday, Prime Minister Lee Hsien Loong announced a Cabinet reshuffle. This is the third since the start of this parliamentary term in January last year.
The first was in October last year when the notable shifts were the promotion of Mr Ong Ye Kung and Mr Ng Chee Meng to full ministers.
The second, at the end of April, or four months ago, saw Mrs Josephine Teo and Mr Desmond Lee become full ministers and Dr Lam Pin Min, Dr Janil Puthucheary, Dr Koh Poh Koon and Mr Chee Hong Tat promoted to senior ministers of state. Mr Teo Ser Luck, a mayor and senior minister of state, it was announced, would step out of public office.
What we have just learnt is that PM Lee has nominated Mr Tan Chuan-Jin to be the next Speaker of Parliament. Replacing him at the helm of the Ministry of Social and Family Development (MSF) will be Mr Desmond Lee.
In explaining his decision, PM Lee emphasised that Mr Tan remains an "important member" of his team though in a different role, which means that the switch-out is intentional, rather than one of expediency - it is not to fill a gap temporarily.
In fact, PM Lee's statement that Mr Tan has the "temperament and personality" for the role of Speaker strengthened the impression that his decision was very much based on considerations of Mr Tan's intrinsic qualities. Mr Tan was acknowledged for having strong networks in the social and sports sectors that remain valuable to that governing team.
Those who have been studying the process of leadership renewal will conclude that Mr Tan is out of the running to be Singapore's fourth prime minister, leaving the main contenders to be Minister in the Prime Minister's Office Chan Chun Sing, Mr Ong and Finance Minister Heng Swee Keat. While the role of Speaker is an important institutional and ceremonial one, it does not involve taking the lead in giving strategic input on policymaking in government.
Many would have thought that the position of Speaker, vacated now by Madam Halimah Yacob stepping down to make a bid for the presidency, would be filled by a senior backbencher, so this is indeed a surprising move.
This is the second such surprising move with regard to those who have been identified as candidates for the position of Singapore's fourth prime minister - those who are in their 40s and were pulled out of leadership positions elsewhere and quickly placed into ministerial positions soon after a general election.
The first was when it was announced that Mr Chan would move from being minister at the MSF to become deputy secretary-general at the National Trades Union Congress (NTUC) and a Minister without portfolio in the Prime Minister's Office in January 2015.
However the difference is that at the same time that Mr Chan became secretary-general , his predecessor, Mr Lim Swee Say, moved from NTUC to head up a "mainboard" ministry - the Ministry of Manpower, thereby setting the precedent for the reverse move.
Does anyone think that the same reverse move could happen to Mr Tan - from Speaker back to Cabinet?
Another key development from yesterday's announcement was that Mr Desmond Lee and Mrs Josephine Teo have been firmly installed among the corps of fourth generation (4G) Cabinet leaders.
These moves signal progress in the leadership renewal process. Some personalities move up, others move out.
These whet public appetite for further clarity on who will be the next premier - the hot topic at many a lunch and dinner conversation since the General Election in 2011, the first election when it was declared that the hunt was on for the 4G leaders.
Indeed, bigger moves are due - the serious candidates for premiership are likely to be shifted into the position of deputy prime minister by the end of this parliamentary term.
However, these conversations tend to revolve around who "they" will choose, as if no one else has a say in the matter apart from the tightest inner circle of leaders of the ruling People's Action Party. Is that true? What might be the considerations that feed into that choice, and who decides?
In this age of great uncertainty where the consensus on how the global economy, international governance and geostrategic politics should work is fraying, the notions of who is a good leader for a small state like Singapore are also being redefined. Our leaders' steady and skilful management of Singapore's relationships with key powers will become increasingly critical.
While it is often said that all politics is local, in recent months, from discussions on Singapore-China relations, we know that that dictum may not be quite so true in Singapore. Singaporeans are judging our leaders, fairly or unfairly, by how they think our government handles that.
While the Cabinet is always a team and therefore a composite of different strengths and qualities, the question is who will be that leader of leaders. That will be defined by what are the present and future challenges we face as a country, and who can win the confidence of Singaporeans to lead us through to that future - this is where the public comes in.
Will Singaporeans prioritise our external interactions and prefer someone with strategic acuity and international standing or is a visionary innovator and risk-taker who leads the country in new directions?
Or will they prioritise a domestic focus and prefer someone who is more deeply embedded in local networks, delivers excellent public services and empowers Singaporean changemakers in industry and society to be the world-beaters?
A frequently asked question is: Will it matter what race this person is? Who can forget that our founding prime minister, the late Mr Lee Kuan Yew, said that he set aside his preferred successor because of his race? And we will be reminded that the current Prime Minister justified the upcoming reserved presidential election by saying that politics in Singapore is not post-racial. This, too, is an issue that lies at the doorstep of ordinary Singaporeans to resolve.
Our conceptions of governance and political leadership shape the decision on who that fourth PM will be. We cannot dodge that responsibility. But if we recognise it, it also means we have that further responsibility of seeking to grasp what our national interests are before we judge who best represents those and who we can have confidence in.
In October last year, PM Lee said that building a leadership team is one of his top priorities. To what extent will those choices be just his; his potential successors'; or ours as ordinary Singaporeans?
• The writer is deputy director (research) at the Institute of Policy Studies, National University of Singapore.
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