Everything about the Trump Presidency is laid back blase BS. There is one of 3 possibilities I personally see by playing the Presidency fast and loose like this:

1. Something will bite trump in the ass that will highly embarrass him, and he will sober up to the fact that he needs to take this job serious. (That is the best case scenario.) 

2. Something will bite Trump in the ass and result in something hurting the US on an international level, and result in fallout on the international level. Take your pick what this is? NK invading SK for some reason. Trump pulling out of NATO resulting in Russia invading someone somewhere due to the chaos that ensues, etc.

3. Something that trump does in the US will cause a cascade effect at home. I can't claim to know what that would be, because its far too early in his presidency. Economy, race relations, etc. Its too soon to feel the fallout of climate change. Who knows.

But I can guarantee you one of those things is going to happen.