Senate Republicans and the White House reached a bipartisan compromise on giving the Congress a stronger voice on the approval of any nuclear agreement with Iran.  Just because they’ve agreed on terms for the debate doesn’t improve the chances for approval have increased.

There’s a widespread feeling in Washington that Republicans will oppose any agreement made by the Obama administration, opting instead for making it a 2016 campaign issue.  The GOP message is already taking shape:  Obama has been a wimp, our allies worry that we aren’t reliable enough and our enemies are not as scared of us as we will make them.

The compromise Corker-Cardin bill is a victory for the Senate in asserting its influence, but some may come to regret their support.  Those are the senators running for the White House because this bill will be a precedent for tying the hands of the next president not only on this issue – whatever the outcome of these negotiations, the repercussions of the Iran negotiations will continue well into the next several administrations – but on all future executive agreements.

 “It’s not Obama that they will be weakening but the office of president,” warned congressional foreign policy expert Howard Diamond.

There's another part to this story.  Sen. Bob Corker (R-Tennessee) is the chairman of the Foreign Relations Committee and he will have some difficult choices to make.

Two roads diverge on Corker's path to history for Sen. Bob Corker as he charts his and the Senate’s course on the anticipated nuclear agreement with Iran.

Each road was traveled by a legendary Republican chairman of that committee, Henry Cabot Lodge of Massachusetts and Arthur Vandenberg of Michigan. And each man held strong beliefs on foreign policy but very divergent views on which path to follow. One is remembered as a spiteful obstructionist and the other as a man who played a major historic role in America's international leadership.

Read more about them in my Washington Watch column.