Respectfully, you and I have deep disagreements. That is because you very much disagree with anything cognizable as the conservative movement. Paleo conservatism is the ideology of the old Eurodiployakkers who wept over the demise of their way of life when WWI broke out. Secret covenants secretly arrived at created the spaghetti bowl of interlocking commitments without which WW I would never have been possible but, never mind....
Blood and soilism is NOT conservatism. Bismarck was NOT a conservative. Neither is the Rockford Institute, Chuck Hagel, Weepy Walter Jones, antiwar.com, Justin(e) Raimondo, or paleoPatrick on matters of foreign and military policy.
Leadership has the obligation, ummm, to lead. That's why they call it.... The US troops were already in Europe (bear in mind Patton's views on the similar situation at the end of WWII). Some were closing in on Ekaterinberg when the Romanovs were massacred. That Lenin died in bed is a moral indictment of Wilson. In 1918, there were capable green and white armies in the field attacking the red and deserving of our assistance.
What justification?????? Lenin, Stalin, Trotsky were Marxist-Leninists who murdered their way to control of a major nation with massive resources. No more justification necessary.
Do I know the future? As Richard Weaver wrote: Ideas have consequences. The soviet idea had obvious consequences to come that needed preventive war.
BTW, Cain killed Abel and then whined that he was not his brother's keeper. Paleos and other foreign policy liberals and wimps NEVER want to assert their moral obligations by way of action in defense of their brothers. It was Cain's way of saying: "Don't blame Cain, Cain is a paleo who was minding his own business."
I do not know from what direction new dangers may arise. That is no excuse for paralysis. As Ted the Swimmer might say (another Cain lookalike), we will cross that bridge when we come to it. We should also remember that an undue adherence to consistency is the hobgoblin of....
Your optimism is very fervent.