With a tweet posted on Thursday, President Donald Trump dismissed five decades of international consensus on the status of the Golan Heights, Syrian territory seized by Israel in 1967 during a preemptive war, declaring that the United States would recognize Israel’s annexation of the region.

Offered without explanation, the move looked to many Israeli, Palestinian and American observers like a transparent attempt to boost the reelection prospects of Trump’s embattled ally, Prime Minister Benjamin Netanyahu, who faces corruption charges and could be defeated at the polls next month.

In reply to Trump’s tweet, Mohamed ElBaradei, the former head of the International Atomic Energy Agency, suggested that the American president “might want to consult with your international lawyers.” Trump’s declaration, ElBaradei noted, flies in the face a United Nations Security Council resolution adopted unanimously in 1967, which called for the “Withdrawal of Israel armed forces from territories occupied” in that summer’s conflict — including the Golan, as well as the West Bank, East Jerusalem and Gaza — and emphasized, “the inadmissibility of the acquisition of territory by war.”

It was not lost on some analysts that U.S. recognition of Israel’s right to annex territory it seized by force would also seem to pave the way for Trump to recognize Russia’s annexation of Crimea.

Calling Trump’s declaration, “a brazen violation of international law,” which “doesn’t change protections occupied Syrians of Golan have,” Omar Shakir, the Israel and Palestine director of Human Rights watch, observed that “moves like this only isolate the U.S. further from international consensus and make its voice even more irrelevant.”

Standing alongside Secretary of State Mike Pompeo, who was in Israel for the announcement, a beaming Netanyahu described Trump’s gift to his reelection campaign as “a miracle of Purim,” the Jewish holiday celebrated this week.

“He did it again,” the Israeli prime minister said of an American president who seems determined to make every wish of Israel’s far-right nationalist leader come true. “First, he recognized Jerusalem as Israel’s capital and moved the U.S. Embassy here,” Netanyahu said, “then he got out of the disastrous Iran treaty and reimposed sanctions, but now he did something of equal historic importance — he recognized Israel’s sovereignty over the Golan Heights.”

By accepting Israel’s 1981 annexation of the Golan Heights, after withdrawing from the Iran nuclear deal and moving the U.S. Embassy, Trump also checked off another item on the pro-Israel wishlist of one of his biggest donors, the American casino magnate Sheldon Adelson, who spent more than $20 million to support his 2016 presidential campaign, and is also Netanyahu’s most important backer.

A measure of how far the White House has tilted in Israel’s favor since Trump took office can be seen in reports from 1981, when Israel’s annexation of the Golan Heights prompted President Ronald Reagan to respond by ordering a halt to a military cooperation agreement with Israel. The U.S. and the entire U.N. Security Council quickly approved a resolution stating that “the Israeli decision to impose its laws, jurisdiction and administration in the occupied Syrian Golan Heights is null and void and without international legal effect.”

As the Israeli-American journalist Mairav Zonszein noted, Jason Greenblatt, the Trump administration’s peace envoy for the region seemed only mildly less excited by the news than Israel’s prime minister.

The American envoy — who is working with the president’s son-in-law, Jared Kushner, on a peace plan that seems to begin with total surrender to every Israeli demand — effusively thanked Trump for a “bold, courageous, and historic decision” by a president “who understands Israel and its security needs.”

“Thieves,” was the concise description of the move from Ali Abunimah, the Palestinian-American activist and writer whose book, “One Country: A Bold Proposal to End the Israeli-Palestinian Impasse,” calls for a one-state solution to the conflict, with equal rights for Israelis and Palestinians. “But it’s good that the U.S. makes explicit its bias and removes once and for all the pretense that it was ever an ‘honest broker,’” he added.

Since Trump has now declared his support for Israel’s previously unrecognized annexations of both East Jerusalem and the Golan Heights, speculation naturally turned to what might come next: the annexation of most or all of the occupied West Bank. When Israeli citizens go to the polls on April 9th, more than half a million Israelis who live in Jewish-only settlements in the West Bank will cast ballots. Millions of their Palestinian neighbors, who continue to live under military rule 52 years after the Six-Day War, remain disenfranchised, with every aspect of their lives controlled by an Israeli government they have no say in choosing.

“When Israel annexes the West Bank,” Lara Friedman, the president of the Foundation for Middle East Peace in Washington observed on Twitter, “Trump can just copy-paste this same text, change ‘Golan’ to ‘Judea & Samaria,’ and presto — with one final tweet, the Israeli-Palestinian conflict will be resolved!”

Trump’s decision to cede the Golan to Israel, following his move of the U.S. Embassy to Jerusalem, “pretty much tells us where the Kushner peace plan is going,” Paul Danahar, a former BBC Middle East bureau chief, tweeted. “It will likely recognise all of Israel’s ‘facts on the ground’ across most of the disputed regions. The weakness of the Palestinian Authority will be exploited and when it refuses to accept what’s on offer, the administration will throw its hands in the air, blame Palestinian intransigence and begin to formally recognise Israel’s claims on parts of the occupied West Bank.”

“There is almost an unseemly haste from Saudi Arabia and Israel to refashion the region as they want it while they have what has proved to be the most pliable US administration in modern history where the Middle East is concerned,” Danahar concluded.

Yousef Munayyer, the executive director of the U.S. Campaign for Palestinian Rights, made the same point in a slightly less nuanced way.