Normally, the visit of a world leader to the United States would be arranged by the White House. But in a breach of sense and diplomacy, House Speaker John Boehner and Ron Dermer, Israel’s ambassador to Washington, have taken it upon themselves to invite Prime Minister Benjamin Netanyahu of Israel to Congress to challenge President Obama’s approach to achieving a nuclear agreement with Iran.

Mr. Netanyahu, facing an election on March 17, apparently believes that winning the applause of Congress by rebuking Mr. Obama will bolster his standing as a leader capable of keeping Israel safe. Mr. Boehner seems determined to use whatever means is available to undermine and attack Mr. Obama on national security policy.

Lawmakers have every right to disagree with presidents; so do foreign leaders. But this event, to be staged in March a mile from the White House, is a hostile attempt to lobby Congress to enact more sanctions against Iran, a measure that Mr. Obama has rightly threatened to veto.

In his State of the Union address, Mr. Obama laid out an approach to international engagement that includes shrinking America’s military commitments overseas and negotiating limits on Iran’s nuclear activities in return for a gradual lifting of sanctions. A move by Congress to pass legislation proposing new sanctions could blow up the talks and divide the major powers that have been united in pressuring Iran. Given an excuse to withdraw from talks, Iran could accelerate its nuclear program, curbed for a year under an interim agreement, and force the United States or Israel to use military action or a cyberattack to keep Tehran from producing nuclear weapons.