This article is slightly liberally biased.
Of course Donald Trump is hoping for a dissolution of the European Union, and it’s not a secret.
When you’re talking about geopolitical powers, three most immediately spring to mind: the United States, the European Union, and China. It’s fair to say that the US has to look at the latter two as economic competitors, at least in terms of their potential for growth and development.
Brexit gave Trump a gift he could never have hoped to have: a lever by which he could play around with the integrity of the EU, hoping to see the world’s biggest international alliance dissolve. If the UK managed to draw away successfully (which is part of why Trump keeps floating a positive deal for the UK Post-Brexit, to make it seem that much more appealing), others might be encouraged to do the same, and that could end up neutralising one of the US’ biggest competitors.
You’ll also note that he’s simultaneously (and unsuccessfully) trying to neutralise China into the bargain, but part of the issue with Trump is that he doesn’t understand the complexity of what is involved. The Chinese are beating him at every turn, and the EU isn’t looking likely to dissolve any time soon, particularly when even Brexit has stalled, and the US economy is similarly showing signs of an economic downturn — with GDP predicted to fall, and the stock market taking several tumbles in recent weeks.
Fortunately, things which are a priority for Donald Trump are not a priority for the rest of the world, and there’s little likelihood that his desires will be enacted by the time his tenure in office is over.