The population at large had significant advantages, back then.
For one, the disparity in power between a military and a militia was alot smaller, closer to nil, in fact. So long as you had access to fairly modern weaponry, an irregular unit could hold its own against a professional military force. Nowadays, you have idiots like the Hutaree (sp?) who think their light infantry training, Kalashnikovs and camo outfits will let them take down Washington D.C.
They also didn't have an entire economy devoted to spying on people back then, a system whereby most malcontents are either fucked with continually or thrown in prison from the moment they fail to adjust to societal standards.
I also suspect the disparity in wealth was not quite as wide, which is a depressing thought in and of itself. Modern wars are decided by economics as much as they are by military skill and weapons, and you cannot fight a war with an army who is mostly in debt or with under $1000 in savings (ie most of the US population).
The systems of propaganda were also less developed. I suspect most Americans were well aware the British were their enemies, the bodies of people killed by them being a significant tip-off. Nowadays, the population is so large and dispersed, people have to rely on the media for their information. And the media, as I mentioned before, incline to power unless they can sense real weakness. They're also increasingly recruited from the ranks of the plutonomy, or those with plutonomic aspirations (reporters back in the 60s and 70s mostly came from working or lower middle class backgrounds. Now, they have Harvard and Princeton degrees. They are also more trusting of government and more dismissive of those outside of their social class. This is not a coincidence).
Agarian societies have actually a lot to recommend to themselves, when it comes to representative democracy and decision making, in comparison with modern industrial society.