It has become abundantly clear that the congressional Republicans’ depository of that precious commodity called leadership is on the verge of bankruptcy.

That was made even more evident this week by the action of a majority of GOP senators, at the beckoning of a naive freshman lawmaker from Arkansas, Sen. Tom Cotton.

They signed an open letter to the leaders of Iran in a blatant attempt to interfere in the negotiations between that country and the Obama administration regarding Iran’s nuclear program.

And that ill-advised action came on the heels of an appearance before a joint session of Congress by Israeli Prime Minister Benjamin Netanyahu — at the invitation of House Speaker John Boehner without first consulting the White House — who condemned the talks with Iran and criticized the U.S. president for a deal that has not been made.

The intent of the sophomoric letter, with its overly condescending tone, supposedly was to give the Iranians a lesson on the American Constitution and an understanding that “(a)nything not approved by Congress is a mere executive agreement,” subject to be revoked by the next president or modified by another Congress.

The 47 signatories of that letter, like the House leadership that colluded with the leader of a foreign country, are co-conspirators in a concerted effort to sabotage the nuclear talks between Iran and a total of six nations: the U.S. France, Britain, Germany, China and Russia.

The detractors claim that their concern is protecting Israel, but in truth their feigned fear of Iran and its potential nuclear capabilities is designed for their own political purposes, giving their devoted base another boogeyman around which they can unite.

To be commended for not signing the letter — and, therefore, demonstrating leadership, backbone and patriotism — are Sen. Bob Corker of Tennessee, chairman of the Senate Foreign Relations Committee, and six other Republicans: Lamar Alexander, Dan Coats, Thad Cochran, Susan Collins, Jeff Flake and Lisa Murkowski.

As Obama proceeds to strike a deal with the Iranians that would freeze their uranium enrichment program in exchange for lifting some economic sanctions against the nation, the opposition in this country has insisted on more sanctions and continues to threaten military action.

One of the major reasons Republicans have fought the president on this foreign policy matter is the same as their attacks on his important domestic initiatives like the Affordable Care Act: They are afraid it will work, and Obama will be credited for another great accomplishment, achieved not with their help, but in spite of them.

And, while these congressional naysayers and Netanyahu rail against Iran’s government and some of its former and current leaders, they also forget that a large percentage of the Iranian people admire Americans and have long wished for their country to rejoin the world. Once Iran is again part of the community of nations — something the current negotiations can help make happen — it will be difficult for any leader or group of leaders to take it back in time.

That thought, of eventually normalizing relations with Iran and getting rid of the old boogeyman image, has to be a scary one for Republicans whose main political tactic has been giving their constituents something to fear.

Bob Ray Sanders is a columnist for the Fort Worth Star-Telegram.