Let’s face it. Presidential debates — especially primary debates — are significant only to the extent that differences among candidates emerge. For Republicans this cycle, they tend to largely be contests to see who wants a balanced budget the most, who will repeal Obama’s health care reform the fastest and who will be the greatest champion on so-called social issues. With a couple of exceptions, there was not a lot to debate in Ames on these topics — at least among those on the stage.

The issue that did come up in the Ames debate, and on which there is the potential for a real dialogue, is that of America’s continuing involvement in three wars and a bunch of nation-building projects, which are costing too many lives and, absent some serious change in plans, will ultimately cost $2 trillion we simply don’t have.

Despite the fact that poll after poll shows that the American people are ready to ask — and answer — the gut-check question of why we are continuing to risk precious American lives and spend billions per day in Iraq, Afghanistan and Libya, why is it that, with a couple of exceptions, Republicans running for president are afraid to have that conversation? Is it that they are paranoid about appearing “soft” on defense? Is it that they are confusing a willingness to spend less on wars with support for our troops? Or can they just not let go of the costly idea that there is some vested U.S. interest being served by building roads in Afghanistan or participating in a civil war in Libya?

There is nothing “soft” about being smart when it comes to using our military might or simply saying to the world that we are no longer going to foot the bill for almost half of the globe’s total military expenditures. And while it may have made sense to go after Al Qaeda in Afghanistan 10 years ago, why are we still doing it? Al Qaeda moved on to greener pastures long ago. As far as supporting our military men and women, there is no greater support we can provide than to NOT send them into harm’s way in wars we don’t need to be fighting.

Let’s have this debate — and let’s have it within the Republican Party. During the debt-limit negotiations, many Republicans ran for the hills at the mere mention of cuts in defense spending. Why? Our debt and precarious economic condition are the greatest threats to national security we face, and asking ourselves why we are spending trillions in wars that frankly don’t involve threats to our national security is a great place to start toward achieving that balanced budget everybody is calling for.

Gary Johnson is a Republican candidate for president. Johnson served two terms as governor of New Mexico from 1994 to 2002.