If you look at just NATO, most countries are not paying what they promised. Trump has been after them since his first term. Did it help? Sometimes, in order to get noticed, you have to kick folks square in the ass the get a reaction.
Trump is the only politician in my lifetime with the balls to do it.
Can you even imagine what our country would be like today if Trump never ran? We probably would have had President Jeb, and after him a litany of milquetoast leaders allowing the disintegration of the country.