{{show_title_date || "Historic nuclear deal puts US, Iran on path to peace, 7/14/15, 11:08 PM ET"}}

The Iran deal isn’t perfect. But it’s better than another war.

Updated

Now that the United States, other world powers and Iran have reached a final agreement limiting Iran’s nuclear program in exchange for sanctions relief, the action on this historic chance for peace turns to Congress.

The legislative branch, authorized by President Obama to approve the Iran deal, now has great power and responsibility: They can either reject the accord, potentially killing diplomacy and putting the United States on a path to war, or allow the president to implement the deal and solidify American goals of blocking all of Iran’s paths to building a nuclear weapon and making the U.S., its allies, and the Middle East more secure.

RELATED: Obama: Without Iran deal, we risk more war

As Congress debates the merits of the final nuclear agreement, it would be wise to listen to the nuclear and non-proliferation experts who say this agreement will move Iran’s breakout time – the time to produce enough fissile material to produce a nuclear weapon – from the current three months to one year or more. They also point out that the agreement provides unprecedented inspections, monitoring and verification regimes, which would catch Iran if it cheated and “snap back” sanctions in short order. 

Some lawmakers claim that the U.S. can get a “better deal.” But experts say there is no such thing.

Why? A better deal would require more pressure on Iran in the form of more sanctions, which have only worked when the entire international community participates. If the U.S. backs out of the deal, our partners aren’t likely to join us in the re-imposition of sanctions after they all just agreed to the deal on the table. Remember, it wasn’t just the Americans and the Iranians negotiating over the past decade and with great intensity the last few years: The British, French, Chinese, Russians and Germans all okayed this agreement, too. As Nicholas Burns, a former top U.S. negotiator with Iran, points out, the global sanctions regime would collapse if the U.S. walks away now from this international agreement.

The other alternative, military intervention, wouldn’t work and would be extraordinarily costly in blood and treasure. Military experts agree that even a highly successful war with Iran may only set its nuclear program back a few years and it wouldn’t destroy the country’s technological know-how. Intervention could also force Iran to do everything possible to obtain a nuclear weapon.

It’s very difficult to estimate long-term costs of wars. You must calculate long-term health care, interest on debt, opportunity costs, loss of productivity and other difficult variables. Nobel Prize-winning economists estimate the total costs of the Iraq and Afghanistan Wars will run between $4-$6 trillion – nearly enough to fund the U.S government for two years. Now consider that Iran is nearly three times as populous as Iraq, four times larger geographically, and spends $8-$14 billion annually on its military compared to the few billion Iraq spent when the U.S. invaded in 2002.

RELATED: On Iran, no need to speculate about the alternative. We’ve already lived it.

Other experts posit that for just the first three months, targeted strikes on Iran’s nuclear program would cost nearly a trillion dollars, with expanded bombings of some military sites increasing the bill by several hundred billion and a full-scale invasion nearing a whopping $2 trillion.

Again, a war with Iran would likely have unpredictable consequences. Would a military intervention spark a larger war in the Middle East with Shiite militias attacking American assets in Iraq, Yemen and other countries? Iran has been linked to acts of terrorism from bombings to assassinations. If the U.S. or Israel attacked Iran, they could certainly use such tactics on American targets abroad and perhaps here at home. Iran’s naval capacity and anti-ship missiles could attack U.S. assets or start a blockade of the Strait of Hormuz, where 20% of the world’s oil passes, creating a spike in oil prices that would have a deleterious affect on the entire world economy.

The most important cost to consider is human. The wars in Afghanistan and Iraq have caused nearly 7,000 U.S. deaths, left well over 50,000 Americans physically wounded, countless mentally and emotionally scarred and, some claim, over one million civilian casualties. It would be difficult to predict the causalities from a war with Iran, but with the likely outcome not solving the problem, it’s clearly not worth the human or financial costs.

The international agreement with Iran keeps it from a nuclear weapon for a decade at least. There is no better agreement to be reached. The alternatives would fail and their price is unacceptably high. While it’s not a perfect path, it is the only path Congress should support publicly and vote to approve. I am contacting both my Senators and my Representative to tell them just that. I hope you’ll join me.

Paul Kawika Martin is the political and policy director of Peace Action, the largest peace group in the U.S. He can be reached on Twitter @PaulKawika.

Iran and Nuclear

The Iran deal isn't perfect. But it's better than another war.

Updated