Is NATO actually alive right now? Is it functioning? We aren't actually observing it, so we cannot know. It's existence is a wave function that has yet to collapse. What would cause it to collapse? Somebody attacking a NATO country.
If ISIS, al Qaeda or whoever, were to attack Norway, and we could track that back to some faction hiding out in what Trump calls a "shithole" country in Africa, the US would commit its forces to the defense of Norway. Why? Hmmm.... Norwegians versus "shithole" countries... our David Duke-endorsed President would love to fight that [race] war.
On the other hand, what if Vladimir Putin were to start encroaching on, say, Estonia? I didn't pull this out of nowhere. The US Ambassador to Estonia just resigned because Trump is being such an asshole, and the question of NATO defense of the Baltics against Russian encroachment became an issue in 2016 because Trump said that the US might not defend them if they didn't pay up. Considering that Trump is upping his financial demands, this is a very real question.
Right now, be honest. If Putin started pushing on the Estonian border, NATO would be obligated to defend Estonia. Do you seriously think Trump would follow through? No. Of course not. He'd bash Estonia, gush about how awesomely "tough" Putin is, yell about how horrible Europe is, and say that everyone needs to pay up, like a fuckin' mob boss running a protection racket. Anyone who says that Trump would ever stand up to Putin is either lying or a fool.
Trump just went over to a NATO meeting, started stupid fights with our "allies," and then talked about how great it was going to be when he met with Putin. The guy who invaded Crimea. A treaty that is only operative as long as it is never invoked isn't a real treaty. It is Schrodinger's treaty. That's what happens when the American people elect Vladimir Putin's stooge as their President. Donald Trump will never confront Putin directly. Therefore, nobody in NATO has any protection from Putin, regardless of what the text of the treaty says, for as long as Trump is President.
Right now, NATO's goal is to ride out Trump. Trump demonstrates a core problem, and it is a core problem that every theorist going back to Machiavelli understood. It is dangerous to depend on alliances with anyone more powerful than you are. Europe has depended on an alliance with the US. From the US's perspective, that alliance has been based on an ideological commitment to western-style liberal democracy, and that is why we have shouldered the financial burden. What do we get out of it? A world order that is to our ideological liking. Trump, though, doesn't believe in that. He believes in autocracy. He hates democracy, doesn't get along with any government built on democracy, and worships totalitarian dictators. So, he's fine shredding a treaty and treaty organization that exists to protect western-style liberal democracy. If the result is more totalitarianism in the world, that's fine with him as long as he's one of the totalitarian rulers. I really wish that I weren't in the position of writing this. This is the kind of stuff that is supposed to be on a weirdo, conspiratorial FaceBook page for someone in a tin-foil hat, not a political science professor's blog. Unfortunately, this is just our world. The President aspires to be a totalitarian ruler. He isn't one, but that is his goal.
NATO is just hoping that, in 2.5 years, that won't be our world anymore. They are hoping that America comes to its senses, kicks Trump out of office, and elects someone with a brain, a conscience, and no aspirations of being emperor. The problem is that all it takes is one chip to demonstrate that the US can't be trusted, and NATO becomes... nothing. All you have to do is look inside that box. Just one quick peak, and the wave form collapses.
Will Putin do anything? He isn't going to march into Eastern Europe with an army of furry hats and scary, Soviet-style music playing in the background. He doesn't have the money, and he isn't reckless. He also doesn't have to do it in order to collapse the wave form. All he has to do is push far enough that NATO would be required to intervene, show that Trump won't, and that sequence would be enough to demonstrate that NATO doesn't work. That would be enough. Dayenu. If, at any point in the next two years, Putin pushes some troops past the Estonian border far enough that NATO would be required to respond, and Trump refuses, NATO is dead because it demonstrates that the largest partner cannot be trusted. Putin will have won, with very little troop commitment.
Right now, because we are not observing this sequence, we are pretending that NATO fully operates. There is some probability of NATO being in effect, for any given eventuality, but that would depend on what that eventuality is. If it gives Trump the kind of race war dynamic that he loves, David Duke-endorsed racist that he is, then we see NATO operating, and it continues to exist. However, NATO is teetering on the edge, and Putin doesn't have to do much to destroy it because the current US President is a lying, backstabbing sack of shit who won't obey our treaty obligations the way NATO did after 9/11, who is probably in Putin's back pocket, who doesn't value western-style liberal democracy, and who, fundamentally, demonstrates his own point. The US cannot be trusted. Under Trump, it cannot, but as long as the trustworthiness of the country depends on the president, the country is not trustworthy.
NATO, though? Raise your virtual hand if you want to look inside that box.