The New York Times reports: The decision by Senator Chuck Schumer to oppose President Obama’s deal to limit Iran’s nuclear program rattled the Democratic firewall around the accord, but supporters said Democratic defections in New York and South Florida would not be enough to bring down the agreement.

Republican leaders in the House and Senate have promised a vote in mid-September on a resolution to disapprove the nuclear accord between Iran and the United States, Germany, Britain, France, Russia and China, which in itself would be a blow to Mr. Obama’s prestige.

But to scuttle the Iran nuclear deal, opponents have two high hurdles. They will need 60 votes in the Senate for a resolution of disapproval to overcome a filibuster by accord supporters. If they get that, the president will veto it. Then opponents must secure two thirds of the lawmakers in both chambers to override the veto.

Mr. Schumer, of New York, the third-ranking Democrat in the Senate and likely Democratic leader in 2017, said Thursday night that he would vote for the resolution of disapproval and a veto override. Mr. Schumer’s voice is powerful, and his politics are wily, but he alone cannot stop the international agreement. [Continue reading…]

As M.J. Rosenberg has pointed out, Schumer believes that it is his God-given mission to serve in the U.S. Senate as the guardian of Israel.