Trump's is known to be an unpredictable politician, one never knows what he is going to pull off from his sleeve. Nobody was expecting to see the United States going into a full tariff wat against both Mexico and Canada.
He is a volatile president for sure, but the risk also consequently increases with such bets which is why you should only invest what you are willing to lose.
The risk increases, but also increases the fun and the thrill one can feel when betting in these particular markets related to politics, is there anywhere else or any other country in which you could bet on so many things as with this new Trump administration?
You are giving too much credit to Trump, it's not him who is making betting on the US presidential election or actions progressive, revolution is inevitable in gambling with or without him and all that we see now aside from the trade war could still happen if he lost the election.
My point is that the US as a country should rather take the praise, not Trump, that is why you see that no country has a lot to relevantly/popularly bet on but the US. Is it Trump who made the US what it is today? Certainly not.