02/17/2015 12:26 pm ET Updated Apr 19, 2015

When It Comes to Iran, Don't Follow the Iraq Playbook

KAREN BLEIER via Getty Images

I observe the recent Washington conversation on Iran nuclear negotiations with a creepy sense of déjà vu. It makes me recall the congressional debate -- if it can really be called that -- in the lead-up to the 2003 invasion of Iraq. Then, as now, political posturing and the embrace of arbitrary deadlines obscured the facts and drove our country into disastrous war with repercussions still playing out today.

Before we get to that, it is important to establish the core points that the overwhelming majority of Americans agree with when it comes to international diplomacy with Iran: Limiting Iran's nuclear program is a priority for the United States and for our allies; any agreement must be enforced with a strict and intrusive verification regime, and there are reasons to be skeptical of Iran, so negotiators should proceed with caution.

These are not the only bottom lines, though. Another is that we expect Congress to do everything in its power to avoid another war. Yet that is the path we will be on if members of Congress insist on disrupting and undermining the diplomatic process.

As Army Major General Paul Eaton, who commanded U.S. training programs in Iraq, put it, "People in Congress who root for the deal to fail have not thought through the alternatives, which are stark: The Iranian program will be limited diplomatically or we will have a war."

Plainly stated, avoiding another war means supporting the current policy of diplomatic engagement -- so long as it is working.

This is where the arbitrary deadlines come in.

Since talks between Iran and the international powers began in January 2014, the negotiations have been extended twice. The goal now is to come to a negotiated agreement by July of this year.

Extending the talks might be a problem if Iran's program were growing. It isn't. In fact, the opposite is true: More progress has been made in the last year containing, controlling, and gaining access to Iran's program than was made in the prior eight years.

In other words, so long as negotiations are ongoing, we are winning.

Unfortunately, some U.S. senators, playing politics, have glommed on to an arbitrary deadline by which to impose additional U.S.-only sanctions on Iran, despite the fact that neither our own negotiating team nor any of our allies agree with that approach. They have set a goal of March for a vote and want to foreclose the possibility of another extension.

All our negotiating partners, including our three most important NATO allies -- England, France, and Germany -- agree that new U.S.-only sanctions will blow up the talks by giving Iranian hardliners exactly what they want: an opportunity to argue that Iran's new policy of engaging the West is failure. And if the hardliners win that debate, they'd work to abandon the talks, kick out the international inspectors, and resume the nuclear program.

This is where we come back to Iraq: In the run-up to the invasion, various arbitrary deadlines were established, and members of Congress felt compelled to look strong, despite the fact that international on-site inspections were working and any Iraqi program was stopped in its tracks. Those deadlines were more about politics than national security.

In the end, Congress failed the country on Iraq. They failed to do everything in their power to avoid a war. Over 10 years after the invasion, thousands of Americans have been lost, and thousands have come home scarred, physically, psychologically, or both. Countless families suffered, and our country incurred more than a trillion dollars in debt.

Ultimately, the negotiations cannot go on forever. Nether Iranian politics nor American politics will allow that. The Iranian negotiators need to secure tangible sanctions relief, and the United States and its partners need to achieve lasting limits on Iran's program. Arbitrary deadlines won't help, though. They will just create unnecessary crisis points and force unreasoned decisions.

As members of Congress think about how to vote, they should heed the warning in another of General Eaton's arguments: "The only military way to stop Iranian nuclear ambitions is a full-scale ground invasion and subsequent regime change. A mission that would make the Iraq and Afghan wars look like a cakewalk."