I agree but...
Couple major things in regard to the Ukraine war.
1) Russia never would have been able to build those multiple lines of fortifications...they'd be under relentless attack from aircraft, drones and guided missiles/artillery.
2) The US reach with cruise missiles ect would extend far beyond the battlefield.
I think we’d be very leery of going through door #2 because we’re wide open to counter attack if the game is lobbing cruise missiles.