One thing Trump could do that others wouldn't is to quit ties with NATO. As he alreasy haa threaten to do so. This could lead to full blown war with Europe and Russia that would spread like a wild fire towards ww3. I am not even kidding, i know people like to use ww3 as a cliche scare tactic, but this war would in a whole different scale, like something we haven't ever seen before.
I am not sure if his voters care as lot's of them wouldn't understand that it would very much affect them.
However i can't see this affecting betting ratios.
I don't think that Trump supports the dissolution of NATO. What he wants is more contribution from the EU nations. US spends close to $600 billion every year on defense purposes, while the military budget of nations such as Germany and England remains as a small percentage if their national GDP. Trump wants the EU nations to contribute in terms of funds, equipment and manpower. And I don't think that there is anything wrong in what he says. Why should the US subsidize the national defense of EU nations? Doesn't make any sense.