Violence marred the transfer of the U.S. Embassy in Israel to Jerusalem from Tel Aviv on Monday, but the ceremony was more excuse than cause. The Palestinians from Hamas who protested along the Gaza border with Israel were continuing their eternal war against the existence of the Jewish state more than they care about where America puts its diplomats.

The transfer of the U.S. Embassy had been promised by multiple Presidents and American politicians over decades, including Bill Clinton and George W. Bush. The difference is that Donald Trump fulfilled his campaign promise. No less a Trump critic than New York Democrat Chuck Schumer, the Senate Minority Leader, proved the point Monday.

“In a long overdue move, we have moved our embassy to Jerusalem. Every nation should have the right to choose its capital,” Mr. Schumer said in a statement. “I sponsored legislation to do this two decades ago, and I applaud President Trump for doing it.”

What he didn’t say is that while Mr. Schumer talked up his legislation at fund-raising time, he muted his support during the Obama years. The embassy would never have moved without Mr. Trump’s willingness to defy political convention.

The embassy transfer is also a symbolic reaffirmation of U.S. support for Israel. Ties between the two countries frayed during President Obama’s two terms, as Mr. Obama made concluding a nuclear deal with Iran his top—really, his only—Middle East priority. One of Mr. Trump’s projects has been to restore better relations with U.S. allies, and in the Middle East that has meant Israel and the Sunni Arabs in Egypt and on the Arabian peninsula.