Lyn, Russia has 700k active military, at least, with 2 million in reserves. If Putin decided he wanted to be in Berlin, and went straight through Poland, he'd be there in probably not much more than two weeks, assuming no U.S. intervention or use of nuclear arms.
For example, Germany is a great country, economically, and perhaps socially, if you like that system, but in terms of military might, well, you guys (Europeans) are militarily sophisticated, but your sheer military force isn't even third-rate compared to the PRC or Russia. At a certain point, even in modern warfare, numbers will tell. And German weaponry, while good, is not good enough to go up against 1.5 million Russians. Sorry, it just isn't.
And that's Germany. Let's not talk about some of the others.
That's why, incidentally, the U.S. has pushed NATO so hard. It really isn't - if you look at past history and actions - just about a sphere of influence or selling weapons...although one would have to be blind and deaf to think that isn't part of it, true. It's been about the fact that the USSR really was an aggressive foreign policy player (not claiming that we weren't), and there is no way to deter a country the size of Russia from doing what it wants in Europe without all of the smaller nations following a "attack one, you attack us all" policy.
Should we want to deter Russia from increasing its influence on Europe? Well, that's for Europeans to decide. Most of the people who actually live close to Russia don't seem to like the idea.
As for the E.U., saying that the E.U. is more powerful than the U.S. only works if you believe that statistics outweigh reality. The E.U. is a loose coalition of independent states, often fractured, usually heading in several different directions, and, currently, rather in a bit of trouble. The whole system reminds me of the Articles of Confederacy that the U.S. colonies tried before the Constitution.
The reason that the U.S. has been having so much trouble in terms of military actions recently has nothing to do with declining power. Indeed, the U.S. is more powerful now than every before - the perception of declining power is due to the fact that other states are catching up, to a degree. That said, to portray this as an inevitable decline in American power is questionable - others are catching up, but, so far, not very much. Right now, assuming no nuclear war, the United States could easily crush any of its potential competitors, and probably two at once.
Rather, the problem the United States has is that it has been trying to embrace a humanitarian sort of war, a war in which, if you are not actually avoiding collateral damage, you can at least look like it. If you were to put someone with the war morality of the 1940s in control of the U.S. tomorrow, there would be no ISIS. There might be rather a lot of dead civilians, but ISIS would be gone.
I'm not arguing for that. I simply maintain that trying to interfere, without being willing to go all the way, is a fools errand. I don't argue that the U.S. should become isolationist, I argue that we should leave NATO because protecting Europe isn't worth the cost, whatever happens to Europe. Besides, France and the U.K. have nukes, let them deter Putin. Or not. It's not our problem, and if Putin ends up as master of Europe somehow, we can just trade with him.
I also don't think that we should be running around the world trying to prevent genocides or overthrow regimes. Every time we do, we either kill way more innocent people than might have died otherwise,
or we create the circumstances for an even worse regime later. This is not always the case, but it is enough of the time to convince me it's a bad idea. So if we decide that we have a national interest in Iraq, for oil for example, we don't go in trying to liberate people and set up a government. We go in, take the oil, and kill anyone who tries to stop us. Or, you know, we can buy the oil for less than the cost of invasion.
As it is, we went in, and we didn't get the democratic government we wanted, or the oil either. Yay.
Incidentally, if you want to know what I would do as the leader of the U.S...well, I would pull out of pretty much every foreign country except Korea. I would focus on maintaining dominance within our own hemisphere, and I would open the U.S to unlimited immigration (but not emigration) from around the world.
As for Empire...you had better damn well hope the U.S. never becomes a true empire. The U.S. has so far acted more like the old Roman Republic, so far as I can see. More of an emphasis on alliances, and persuasion. Get an analogue of someone like Titus Vespasian in charge, and the world would be a much nastier place. That's true for the PRC as well, btw. Both the U.S. and PRC have behaved much more diplomatically than they technically have to, given the disparity of strength between them and their neighbors. That's not to say that they've acted
morally, it's just to say that, compared with the British Empire or the Roman Empire, they've been far less, well, imperial.