If other Presidents from different countries have taken attention to Bitcoin and the whole Cryptocurrency Industry, President Trump is also capable of doing that. It just depends on whether how he will take the information regarding Bitcoin. If he sees it as an opportunity on where the government can benefit, he might place some rules and regulations regarding on how to use it BUT if he sees it as a threat, then he can possibly ban it.
I think that will depend on the countries that we are talking about. There are countries that he have some alliance with and there are those that he don't like and if we will be talking about those countries that he doesn't like, I think there is a high possibility that he will be banning it. He might also find a way to counter it, maybe a way to fight it.