I would posit that it's likely pretty much the same for any powerful nation, with the exception that in some places, slightly less of a pitch has to be made to any random person in the nation. Though one may emphasize the point that in america, they seem to go ahead and do stuff anyway, with the rhetorical arguments just standing in for the frosting on the cake of it.
Yes, that seems to be true. The US government and media often present a very oversimplified version of the world for the sake of public consumption, with a lot of vague talk about patriotism, along with a good deal of melodrama, usually involving the so-called "free world" vs. whatever form of "evil" we happen to oppose. Some people might buy it, but others might be a harder sell, so that's when they get pitched the national interests position.
This is especially true, if it doesn't appear that there's any immediate threat to our national soil.
I think before one can understand what a national interest is, one might have to understand what the concept of sovereignty is. Sovereignty for whom, or what? The documents that underwrite a nation, the laws? The individuals in it? The leaders? The motives? To the degree that all humans on the planet seem to share some general motivations, how are those really nationalized?
These are all excellent questions. I consider a sovereign nation to be one that's independent and which makes its own laws and governs itself. How it governs itself would be considered to be its own business. If it's a dictatorship and the people rise up and overthrow it to form a free and democratic government, it would still be sovereign regardless - unless an outside power invades or intervenes, in which case their sovereignty would be in jeopardy.
That's where it can get a bit dicey, since some countries might be in a position of disadvantage or weakness to the point where they can be easily subdued or dominated by larger powers.
Did a russian fighting in afghanistan understand more about why he was there than an american?
I can't really say. However, considering that Afghanistan bordered the USSR at the time, it might have been easier to sell the idea of a hostile nation right off their border, which could have been a threat to their national territory. Likewise, Americans might be easily convinced that military actions close to America, such as in Panama or Grenada, might be necessary for our national protection and sovereignty. But when it comes to sending troops to far-flung places like Afghanistan and Vietnam, our leaders have a lot more explaining to do.
With Afghanistan, it was initially to try to find Osama Bin Ladin, capture him, and bring him to justice. That seemed simple enough at first. Though it took ten years to find him - not in Afghanistan - and then the troops remained there another ten years. That was more difficult to understand.
If most people want 'world peace,' where does that possibly come into conflict with national interests? What if peace is attained, but it appears to be corrupted? Is there such a thing as a corrupted peace?
It could be. The major powers have largely remained at peace, though the wars which break out seem to involve smaller powers fighting each other - or perhaps a smaller power being attacked by a larger power. The major powers will not fight each other, especially if they're nuclear armed. But they may fight through proxies among the smaller nations or factions which may be pliable towards advancing their interests.
In a situation such as during the Cold War, where the US and USSR remained officially at peace throughout, the war was still fought through proxies, in which powers used other nations as pawns. Both the US and USSR were major arms exporters, and would send out trainers and advisors to whatever faction they were backing.
That might be an example of a "corrupted peace," since both major powers were technically at peace, yet with nasty and violent underpinnings. It led to a great deal of death and destruction, but not within the sovereign territory of either major power.
