The post-1945 rules-based order was already a slow motion train crash that most of the West remained in denial about until Putin wiped his behind with it in the 2014 invasion of Crimea. To pretend that Trump is somehow breaking an otherwise intact system at this point is fanciful.
>"The post-1945 rules-based order" - it was always one rule for me another one for thee
The post-1945 order was dead after the NATO's war in Yugoslavia in 1999, and the subsequent recognition of Kosovo. At the very latest.
One coulld argue that it happened earlier, for example after the collapse of the Soviet Union, or the collapse of the Warsaw Pact, or after the annexation of East Germany.