Asked for his reaction to the preliminary nuclear deal reached with Iran, Wisconsin Gov. Scott Walker promised that he would break that deal immediately, on Jan. 20, 2017, his first morning as president of the United States.

When you hear that level of willful ignorance from a leading candidate to be president of the United States, you ought to worry and perhaps even despair.  His answer betrays a refusal to do what any rational person would do in that situation, which is to ask:

OK, and what would happen next?

Because here's what would happen: If the United States breaks the international agreement on January 2017, we become the world's villain and Iran becomes the aggrieved party. They won't be the party that cheated; we will.

In addition, the international arms inspectors who would be monitoring every aspect of the Iranian nuclear program on a 24/7 basis would immediately be kicked out of the country. Iran would have every reason to immediately resume its program at an accelerated pace. Our partners in the unlikely coalition that has enforced sanctions on Iran and helped negotiate this agreement -- Russia, China, France, Germany and Great Britain -- would see our actions as a unilateral betrayal and would not be open to re-establishing those sanctions. And Iran's leadership would have no incentive whatsoever to resume negotiations with a country that had just proved it had been acting in bad faith all along.

What's next? What's next would be war as our only remaining alternative. And it's a curious thing. Those who oppose this deal speak of the risks that it involves, and there are indeed risks. But we have a very good idea of what those risks would be, and we know how to minimize them. As President Obama noted Thursday, if Iran cheats, we will know almost immediately that they are cheating and can take the appropriate steps, including military action if necessary, at that time.

The risks of war, on the other hand, are unknowable. As you may recall, the invasion of Iraq began with lofty promises that we would be greeted as liberators, that the invasion would pay for itself, that we would turn Iraq into a model of Islamic democracy and that other countries in the region, most notably Iran, would be intimidated into acquiescence to our wishes.

Instead, it has led to the creation of ISIS, the vast expansion of Iran's influence, the undermining of political stability in the entire region and a cost to taxpayers of some $2 trillion, not to mention the loss of more than 4,000 American lives. By comparison, war against Iran would be much more complicated, much more difficult and much more likely to produce unpredictable blowback.

As governor of Wisconsin, Walker can't be expected to have a detailed, sophisticated understanding of global politics, and I don't in any way mean that as a criticism. It's just a fact of life. On the other hand, this isn't three-dimensional chess, nor does it require in-depth knowledge of nuclear physics or the intricacies of Middle East politics. It merely requires the willingness to think things through, to ask the obvious question:

"What happens next?"

After you've blustered and postured and quelled those apparently nagging doubts about your masculinity, after you've actually engaged the mind that the good Lord gave you, what happens next?

Unfortunately, Walker is far from alone, because a lot of the other reaction to the Iran deal has been equally mindless and predictable.

U.S. Sen. Mark Kirk, Republican of Illinois, offered the helpful observation yesterday that “Neville Chamberlain got a better deal from Adolf Hitler” than Obama got from Iran, an attack that by now qualifies as the hackneyed mark of an lazy intellect.

If you know American history, you know that every successful peace-making venture since the end of World War II has been attacked in terms of Chamberlain appeasement. And you know that every war that we have fought, including the tragedies of Vietnam and Iraq, has been sold to the American public as necessary to avoid the dangers of appeasement.

Here's a few examples:

  • When Richard Nixon returned to Washington from his historic trip to Communist China, he was condemned as an appeaser and greeted at the airport with protesters huddled under black umbrellas, the personal symbol of  Chamberlain.
  • After Jimmy Carter negotiated the SALT arms-control treaty with the Soviet Union, he too got the treatment, with Donald Rumsfeld warning that "our nation's situation today is more dangerous than at any time since Neville Chamberlain left Munich."
  • When Ronald Reagan met with Soviet leader Mikhail Gorbachev to discuss an arms treaty in 1985, it was attacked as "the most dangerous summit for the West since Adolf Hitler met with Neville Chamberlain in 1938 in Munich." The source of that particular attack? A right-wing congressman by the name of Newt Gingrich.

The specifics of this deal can and should be thoroughly debated. Nobody is pretending that it is perfect; nobody argues that it is without risk. But those elected officials already attempting to sabotage it and undermine it as appeasement have an obligation to explain to the rest of us:

OK then, what next? What's YOUR plan?

And the answer cannot be vague talk of "getting tough," etc. We're past the point of such nonsense; the outcome is too important. This is a national security question of the utmost seriousness. Explain to us what "getting tough" means, in concrete terms. Lay out an alternative course of action, step by step, that would be more likely to accomplish the necessary goals. I have seen no critic of this deal even attempt such an exercise, and my suspicion is that they do not attempt it because, like Walker, they have absolutely no idea what they're talking about.