Prevent what? Trump and the recent rise of right-leaning populist leaders in Europe (Denmark, Hungary, Poland, Sweden, Italy, Austria, Switzerland partly, Slovakia...) was simply the will of the people. Its not "fake news" that has elected these forces, it was the failure of the former mid-left/mid-right government parties to listen to their people and they have been voted out of office rightfully.
There has been signs of Russian meddling via propaganda though.
Nevertheless it’s the people who voted.
If said people don’t wake up and realize that they are being played as “useful idiots” to destabilize their own country ...
Besides the fact that foreign propaganda has played a relevant role, all the countries besides Italy are very good off. The east European countries have been hanging from the EUs tit for years and have grown into good prospering members now. And Switzerland and Austria never had any problems to begin with.
This whole movement grew out of prosperity. Same goes for the US.
Now that they are in force, they either mess up (cutting down democracy wherever it's possible, damaging legal institutions, spreading hate against minorities, hurting the economy)or are on the way there, see Italy. Meanwhile spitting in the faces of those who fed them (see east EU and Italy).
How can you call anything of that "rightful" is beyond me.