Who will they attack first? Greenland? Panama? Canada? Each other? It obviously won't be Russia...
It's really not beyond the realms of possibility that the USA becomes like the Soviet Union and falls apart seeing states turn into countries. It's so fragmented that even the brainwashed "USA! USA! USA!" mentality can't paper over the cracks. I think that we're seeing the beginning of the end of the US "empire".
Imagine the wall building and border guarding that would require. Imagine how quick some states would jump backwards in terms of laws and rights.
The wealthy states already scream about illegal immigration, how do they expect their way of life to continue without vegetable pickers, toilet cleaners, kitchen preparers, prison guards, garbage collection, and the rest of the unsexy non boardroom billionaire work that needs doing.
Once retaliatory tariffs are aimed and land on middle america there'll be a swell of anger, there was a sort of similar issue in the uk at the end of the 80's where coal was being removed and so the jobs had to go. She was asked whilst walking into some meeting about how industry could traverse and so, ordinary people could survive, her answer was "we will train you", to which the poor miner responded "who will feed my family while I'm training?", she was stumped and about faced. Once the foreign markets can't cope with higher pricing, the means to keep the jobs going is over, there is no instantaneous other line of work to step into so the load falls on welfare (and they're already not happy with that ''burden''). There's a lot of suffering about to be unleashed by the new u.s. messiah, sadly they've deep enough pockets to make this a form of siege, he's running the narrative that u.s. friends are actually foe's whilst punitive trade action is taken against there allies. It's perverse, and it gives him the means down the line to point and attribute blame for when the jobs go... "it's all Canada's fault, see, told you all along..."
