TR supported US entry in WW1 as early as 1915.
I know that but again TR cannot unilaterally declare war, he has to get Congress on his side. America could perhaps e more Pro-War with President Roosevelt during the opening of the conflict. I was more specifically speaking about the idea of Theodore Roosevelt doing stupid things like intervening in ever single American nation who is doing something he does not particularly like. The craziest idea is that TR would want to annex northern Mexico. That is just plain foolish.