The irony of history
Most of the time, history is done on accident, typically because of public opinion, but for Thomas Paine, the intent is very clearly to do history on purpose. He talks with unexpected openness and straight-forwardness about how philosophical concepts that few of his contemporaries could have thought up. Paine knows that with cooperation, humans can band together to make historical changes toward a better future.
The irony of British rule
One should expect that when Paine writes about the British government, he might spend his time repeating all the arguments he has against Britain and the throne, but instead he does something unexpected—he tries to step backward to get a better point of view. He notices that actually, Britain isn't the problem—the real problem is that in the West, people haven't really tried to invent a better version of government than monarchy.
The irony of nobles oblige
British monarchy comes with a cultural phenomenon called "nobles oblige" (French for "an obligation of nobility") which is painfully ironic. The idea is that rich people are constantly working to figure out the most honorable use of their power, and hopefully that means they're helpful to society at a large level. Thomas Paine observes the irony of this assumption. Not only does that argument not stand up to scrutiny, it's painfully wrong. There are many rich and powerful people who are amazing and charitable, but the idea that money gives people ethical wisdom is obviously wrong.
The irony of distance
British rule over America seemed only logical to the British, and since the Americans were Brits when they arrived to the New World, it took a long time for Americans to start feeling that they were different than British people. Paine tries to do his due diligence by acknowledging his civic duty as a Brit, but he proposes major changes to British government, but he's too far away from Britain for that to ever have been a real option. The American Revolution was determined by this irony—that Britain was globally over-extended.
The irony of power
Paine talks a lot about power, but he observes that we the people should have the right to revolution because the imposition of power can easily verge on the unethical. Therefore, he feels, since humans are endowed with sovereignty, he feels, humans should have the right to stand against the forces of power. Paine's arguments point to the fragile, unnecessary nature of restrictive government.
