The over-heated debate over whether Congress should block the Iran nuclear accord is done. Finished. Baked. With 41 Democratic senators—and counting—now endorsing the agreement, Congress cannot block the pact. It is time for opponents of the agreement to stand down. If they don’t, they would reveal the partisan political nature of their opposition and their willingness to embarrass the entire nation while the world looks on.

Yes, opponents of the Iran pact may feel bitter that they have lost this fight, and they may want to get even. One way they could do that is by symbolically rejecting the Iran agreement. Republicans in the House have the votes to do that, and in the Senate it’s too close to call.

{mosads}But voting to reject the agreement would be an empty, shallow act. President Obama has promised to veto any legislation that undermines the pact, and we now know that Republicans in the Senate do not have the 67 votes needed to override Obama’s veto.

House Minority Leader Nancy Pelosi (D-Calif.) wrote to her colleagues Sept. 2 that with the support in the Senate and her vote count in the House, “I am confident we will sustain the president’s veto in both houses of Congress.”

Simply put, this means the Iran agreement will go into force. This is very good news for those who want to prevent an Iranian nuclear bomb in a peaceful and verifiable way.

Yet congressional Republicans seem intent on voting down the deal just because they can. At this point a vote against the agreement would be purely political. These votes can have no effect other than to send a message that Republicans do not favor the agreement. But we already know this. Got it. Message received.

There are significant diplomatic costs to voting down the Iran pact, which would be paid by the next president as well as the current one.

Secretary of State John Kerry said Sept. 2 that, “It is hard to conceive of a quicker or more self-destructive blow to our nation’s credibility and leadership – not only with respect to this one issue, but I’m telling you across the board – economically, politically, militarily, and even morally. We would pay an immeasurable price for this unilateral reversal.”

Kerry was talking about what would happen if Congress were to reject the deal and override a veto. But just having Congress force a veto fight would also be damaging.

“There’s a cost to the international credibility of the country and this president if a motion of disapproval passes the House and the Senate,” said Senator Chris Murphy (D-Conn.). “There is some harm to the country’s standing if we have to go through the charade of the veto.”

Are Republicans really going to drag the global stature of the United States through the mud just to score political points against President Obama?

Rather than continuing this battle to the bitter end, it is time for cooler heads to realize that a veto fight is counterproductive. It serves no useful purpose.

Indeed, the legislation (the Iran Nuclear Agreement Review Act) that gave Congress the framework to review the Iran pact made it quite clear that Congress does not have to vote. Congress can simply run out the clock until Sept. 17 and the agreement will go into effect.  And in this case, silence is golden.

It is time to stop this charade. Voting down the pact would only serve to embarrass the president and the United States in the eyes of the rest of the world. It would lay bare for all to see just how broken the American political system really is. It would be hanging out our dirty laundry on the international stage.

For this reason, Senate Democrats must stay united to avoid a damaging GOP political protest vote. These days, all major votes in the Senate must pass a 60-vote threshold, so 41 Democrats can block a vote on the Iran agreement. This would be a much better outcome for the United States and for the future of the Iran agreement itself.

This is no time for the White House or Senate Democrats to rest. They must redouble their efforts to prevent a veto fight that would damage U.S. international credibility. The United States’ global standing is at stake.

Collina is director of policy at Ploughshares Fund, a global security foundation in Washington DC.

Update at 2:20 p.m.