An Israeli flag on Mount Bental in the Israeli-annexed Golan Heights. Photo: JALAA MAREY/AFP/Getty Images

After the Second World War, the international community decided that invading other countries — in order to seize their territory — was a lousy thing to do. So, in order to discourage that behavior, the great powers established laws and norms against recognizing a conquering power’s sovereignty over lands gained through war. This prohibition is the legal basis for international opposition to Vladimir Putin’s invasion and annexation of Crimea.

And Donald Trump just called on the United States to nullify it.

On Thursday, the president tweeted, “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!”

In 1967, Israel invaded the Golan Heights, which lies within Syria’s borders, during the Six-Day War. It effectively annexed the territory in 1981. But the United States has refused to recognize Israeli sovereignty over the area, in accordance with U.N. Security Council resolution 242, which reiterated the “inadmissibility of the acquisition of territory by war and the need to work for a just and lasting peace in which every state in the area can live in security.”

Trump’s tweet coincided with Secretary of State Mike Pompeo’s visit to Jerusalem, and comes two weeks before Israeli prime minister Benjamin Netanyahu will face voters in his bid for reelection. If the president’s post is a genuine declaration of U.S. policy (far from a given), then it represents a major diplomatic victory for Netanyahu.

As of this writing, the White House has refused to tell the public whether Trump was expressing a presidential order in his tweet, or merely a personal opinion. Regardless, the president’s sentiment contradicts decades of U.S. policy, undermines the legitimacy of American opposition to Putin’s annexation of Crimea, and will embolden right-wing forces in Israel who have been pushing for the annexation of the West Bank (a move that would ostensibly make Israel into a de jure apartheid state). It could also provide Hezbollah with a rationale for ramping up violent resistance to Israeli forces in Syria.

But Trump’s reckless words are nevertheless likely to boost Netanyahu’s prospects for reelection. And at the end of the day, that’s (apparently) what really matters.