Sorry, as a Cold War sailor of 11 years who was constantly chased by Soviet surface, subs, and aircraft, any empire builder will still have to deal with our Tridents! Yes, some Tridents have changed out some of their nukes for cruise missles. We still have enough nukes to blow up the world, contrary to popular belief (1 thousand and 5 hundred at least). No nation will ever try to conquer us for that reason alone, not to mention many nations (China&Russia) possess too much of our debt and would prefer not to take those losses.
So let the empire builders try. Besides us, there is England, France, Israel, India, etc. that will keep the idea of MAD going. Of course, there's always the rogue Muslim nations if they can get their hands on a nuke.
But here's a comforting though I learned some time back from a nuclear physicist: All fissionable materials have a nuclear signature from where they were created, whether enriched U-235 or plutonium. Ever wonder why we haven't been nuked yet, even with a dirty bomb? Because it can be traced back to origin.
Even if from some small muslim group, it will still be traced back to point enrichment and through the channels when they got their hands on it. The CIA sometimes misses the boat, but they have thousands tracking fissionable materials. I say thank you.
Plus, the so-called "suitcase nukes" supposedly on the "black market" are now worthless. They need too much constant maintenance. According to the nuclear physicist I talked to they are now non-operational, except for the core which could be used in a "dirty bomb". However, see above about traceable isotopes.
When the average family can afford groceries and gasoline again with a few bucks a month left over, then maybe it would make sense to do for the Europeans what they should do for themselves.
I say we tell the Ukrainians, "If you like your country, you can keep it", and offer ammo along with more veggie MREs. In fact, just cutoff military aid to the Paks and every other Muzzie country then send it to the Ukraine. That's a fat wad of cash and equipment without costing an extra dime.
As for trying to conquer the US by ideological means, a ideological nation has been making the most progress in that in doing so for decades. What is past to another enlightened nation is present to US.
Israel hath cast off the thing that is good: the enemy shall pursue him. They have set up kings, but not by me: they have made princes, and I knew it not: of their silver and their gold have they made them idols, that they may be cut off. (Hosea 8:3-4)
I have written to him the great things of my law, but they were counted as a strange thing. (Hosea 8:12)