There was also the immense domestic repression, including jailing dissidents during WW1.

Also, the racism had a huge impact. The USA was no anti-racist paradise before, but Wilson set matters back a half-fucking century. And in doing so, took an immense amount of energy of decent folk into fighting to claw back the rights of Black Americans.

Exacerbating a problem not only exacerbates the problem, but also reduces resources available for all other problems.