I think it depends. Most European members still do not meet their minimum expenditures on defense, which many Americans are not happy with. We essentially backstop their defense so that they can spend more on healthcare. For the US to stay in NATO, NATO members need to meet their obligations.

They also need to not engage in bellicose actions that are designed to drag the US into a needless war. If no one ever wanted to let Ukraine into NATO, it could have been agreed on with Russia in 2022 and millions of young Ukrainians and Russians would still be alive today. Instead, Tony Blinken and Jake Sullivan decided to see what would happen if they refused to try diplomacy, much like what would have happened in 1962 if the USSR hadn't removed missiles from Cuba.

Europe has gotten into a box it can't get out of. Putin is Hitler and any negotiations are appeasement, and the mantra is "Russia cannot be allowed to prevail", but the reality is Russia will prevail, and by the Summer of 2026 at the absolute latest (assuming total support by Europe at a level able to replace lost US funding), and the only way to stop that from happening is for NATO states to enter into direct war with Russia.

As a result, Europe has no plan as to how to move forward, only pathetic PR statements and some wishful thinking. If Europe continues down this path or, God forbid, wants to let Ukraine in NATO, then the US should give Ukraine the US spot in NATO and run, not walk, away from the alliance.

Finally, NATO was always about projecting US power and influence, and it was clear to earlier generations that this made the European states effectively vassals of the US. The newer generation doesn't like to be reminded of the power imbalance, but Europe combined is only 50% of the US economy, and it's dropping. If they ratchet up defense spending it will be at the cost of more social programs, which an aging and dying Europe cannot afford to cut without risking even bigger unrest than it has seen.

So I guess the US should only stay in if the Europeans start to do what they're supposed to do, namely, meet their minimum spending and shut the fuck up when the US tells them to do something.

No, under no circumstances. Total economic blockades of those states that try is acceptable, military action is totally acceptable as well, up to and including the use of our nuclear weapons against them.

No, under no circumstances. See my response to Question 2, above. The world is already dangerous enough. Imagine a world where the Democratic Republic of Congo has nukes.