The worst mass shooting in the history of the United States in a gay nightclub in Orlando, Florida, is a reminder of how multiple hates and lacunae converged in a single devastating act that has cost nearly 50 innocent lives.

The gunman, Omar Mateen, was an American citizen of Afghan origin who professed allegiance to the Islamic State in Iraq and Syria (ISIS). His act of destructive rage fits ISIS' exhortations to its sympathisers and lone wolves to retaliate against the US for the latter's sustained bombing campaign against the former in Iraq and Syria.

But the choice of Omar's target was telling - it was neither a US government or commercial property nor an educational institution. The fact that he picked a hangout for party-goers who are homosexuals from the Latino community hints at the varied layers of prejudice motivating such militant terrorists, such as the notion that Western societies are decadent and that they encourage "unnatural" and "sinful" activities like gay unions and non-heterosexual revelry.

The "Satan" in the books of those like Omar - who admire ISIS and other hardline Islamist terrorist groups - is not merely the US military and American domination over Muslim lands and rulers, but also a cultural threat which "disgusts" them in their heart of hearts. The two stereotypes of the West as an oppressive colonialist and as a promoter of secular, licentious and debauched values are inseparable in the mental make-up of radical Islamists.

US President Barack Obama said on Monday that Omar had been radicalised on the Internet but that "there is no clear evidence that he was directed externally".

According to Omar's father, the 29-year-old had "become very angry after seeing two men kissing in downtown Miami recently". The belief that lesbians, gays, bisexuals and transgender (LGBT) people are deviants who are upturning God's designated gender roles and norms is not limited to Islamist terrorists. It is a view shared among social conservatives of different religious faiths.

But for those inspired by ISIS, such transgressors of divinely ordained social rules must be mercilessly exterminated. ISIS-governed territories in Iraq and Syria have witnessed a systematic witch-hunt and brazen killings of dozens of alleged homosexuals by hurling them from rooftops or stoning them to death.

In an already orthodox social atmosphere where LGBT persons are stigmatised, ISIS has brought an all-new zeal to dish out exemplary punishment in public spaces to "cleanse" un-Islamic sodomy.

Omar's horrifying shooting spree in Orlando also threw a harsh light on the perennial domestic weakness of the US where even moderate reforms to lax gun controls have not been permitted by the lobbying power of the gun industry. A zealot like Omar who worked as a former security guard could not have amassed heavy weapons and inflicted this much damage without a large support network if he were anywhere else in the Western world.

As President Obama lamented yet again in a familiar and helpless tone after the Orlando calamity, the failure of the American polity and society to restrict access to war zone-calibre weapons has made the job of killers that much easier.

Terrorists take advantage of chinks in the armour of their target countries' legal and political systems. The unhindered access to weapons of mass murder in the US is a product of the capture of policymaking by special interest groups which operate at the level of preventing any new legislation and at the level of propaganda where owning guns is painted as manly and necessary to keep evil "others" (racial minorities included) under control.

Overblown fears of crime and random violence and a definition of American identity as one where freedom and protection cannot be left to agents of state but must be secured by individualised means have created an opening for terrorists to exploit. The US Department of Homeland Security may take any number of policing and preventive measures but it has no remit to restrict the gun culture that has been ingrained in the US.

That an African American like Mr Obama became President and a woman like Mrs Hillary Clinton might succeed him to the White House speak volumes of how democracy in the US is broadening and becoming more legitimate.

However, the saga of endless gun violence reminds us that the problem-solving efficacy of American democracy is rather low. The superpower is a lame duck when it comes to combating entrenched vested-interest lobbies such as defence manufacturers, giant banking conglomerates, the car industry and the pharmaceutical cartels. Enter a terrorist like Omar into this fecund milieu and we get disasters like Orlando.

Polemics in a presidential election year have kicked in to argue that Omar was an Islamist fundamentalist with a political motive and that one must not conflate his crime with that of routine psychologically deranged gunmen who periodically go berserk in America.

But the chilling act in Orlando offers the ultimate negation of this division of problems. It shows how mass crimes by the mentally ill and by the ideologically driven have one and the same catastrophic end result in a nation patently unable to realise the full potential of its democracy.

• Sreeram Chaulia is a professor and dean at the Jindal School of International Affairs in Sonipat, India.