Which wasn't a revolution, Jan 6th or the Civil Rights Movement? The Jan 6th was definitely an attempted coup (unless you ask the MAGA cultists), but the Civil Rights was definitely a revolution of some form. And the Kent State Massacre is just an example of the violent suppression often used by the US government (though we usually prefer it to be in other countries).

The US isn't a dictatorship (yet, who knows where we'll be in 2 years time), but you look at how militarized our police force is and how many US citizens are gunned down by them every year and tell me we that we aren't a militarized police state. Our cops are buying surplus IFVs from the army to drive around in. Palestinian protesters at colleges were having their belongings seized and thrown out by police and administration both - including things like medications. During Bush Jr's administration, you could only legally protest against the Iraq war in areas cordoned off with concrete barriers and fences (sometimes with barbed wire on them). Several studies were done years back by some Ivy League schools looking at laws that were passed or not and their popularity with the 1% vs the majority of Americans, and their conclusion was that the US cannot be considered a democracy and is in fact an oligarchy.

Dictatorships are usually brought down by their own incompetence, but resistance groups speed that up and help keep people from dying. The point isn't open warfare against guys with tanks and beyond visual range missiles, but asymmetric warfare meant to cripple the government's operational capacity for oppression and community support for the population. Like in Myanmar, where resistance groups are fighting against the ethnic cleansing being done by the military using 3d printed guns because not a single nation in the world cares enough to send them aid. They can't get guns, but they can get hobby 3d printers and bullets, and that's good enough to kill a soldier and take his gun.

Like George Washington said when he opposed the Second Amendment, "Farmers with guns will never win against a professional army." But you don't need to, you just need to be annoying enough that the government falls on their own knife trying to catch you. Rambo getting gunned down in a blaze of glory will be remembered as an idiot. The black militia put together and trained by a black WW2 veteran who put down sandbags and machine gun emplacements on people's porches to protect them from retaliation by the KKK are remembered as heroes. Just like the people who showed up for MLK's show of force in D.C. that we call The Million Man March today. That wasn't just a protest. It was a threat that terrified every white suburbanite across the country. If he could mobilize a million people to the capital just to march, what else could he do?