Since this is a US-centric forum, I’ll stick with my views which I think would be most unpopular in the US.
I’m an atheist. Atheists are the most hated group in the US.
I’m a socialist. The US is probably the most anti-socialist country on Earth, where the doctrinal system is virulently opposed to socialism, and disseminates anti-socialist propaganda—misinforming people about what it is, what its ideals are, and what its history even is.
I’m an anti-capitalist. The US is probably the most pro-capitalist country on Earth, where the doctrinal system continually lauds and exalts the virtues of capitalist, and disseminates pro-capitalist propaganda—misinforming people about what it is, what its ideals are, and what its history even is.
I think US neo-colonialism and cynical geopolitical policies of recent decades are almost entirely to the cause of Islamism and the violent reactions of so-called Jihadists. The US supports authoritarian dictators where they just happen to support US political and corporate interests. The US destabilises entire countries where they just happen to be “socialist” or not aligned with US political and corporate interests—leaving power vacuums filled by even worse authoritarian dictators, or warlordism. The US continually supports the criminal actions of Israel, embittering and enraging millions in the region.
I think liberalism a naive and misguided ideology. This would be unpopular with about half of America.
I think contemporary conservatism is inane at best, and psychotic at worst. This would be unpopular with about the other half of America.
“Libertarianism” is disgusting Social Darwinism and mere “liberty” for the owner class to exploit, discriminate, and steal with impunity—whilst reproaching the poor for their own poverty. A morally bankrupt ideology that would create misery and psychosocial dysfunction on a scale not seen in centuries if ever seriously implemented. This accounts for my unpopularity with almost everyone else who is isn’t a liberal or a conservative.