There was a nearly identical situation in 20th century Germany.
Politicians laughed Hitler off as a joke until they got scared and it was too late.

Republican silent pact:
Lets get while the getting is good with a majority and then worry about the after effects.

They are ignoring the aftermath. Even the Generals are saying we are running out of time. Compared to a glacial Congress, time is on the side of Trump who has split second tantrums and narcissistic vengeance.
Tillerson says he will keep talking until the bombs drop.

At our most vulnerable who is to say Russia will not increase infrastructure cold war hacking. China will have choices to make with a USA nuking their border.