I know we've come to expect unusual behavior from the present POTUS, but I really fail to understand the benefit for the US of recognizing Israel as owning the Golan Heights.
For one thing, it overturns the general post-war consensus that nations can't increase their territory through military action. And, well, it doesn't seem like it will do anything except isolate the US diplomatically.
This question shouldn't be construed in any way, shape or form as support for Assad's government. Or a strong desire to force Israel's hand to return it without security assurances from Syria.
This is the full text of the tweet.
After 52 years it is time for the United States to fully recognize Israel’s Sovereignty over the Golan Heights, which is of critical strategic and security importance to the State of Israel and Regional Stability!
–Donald Trump, via Twitter (2019-03-21)
Edit: apologies to both answers given so far, but I'd like to shift the discussion away from the electoral motivations to what concrete benefits the US could expect if this policy was actually implemented. I.e. how is this good "for the US", rather than any political parties.