Here's the dilemma: How do we stop the Islamic State without strengthening the Islamic Republic?
The Islamic State, a growing Sunni jihadist militia, now controls large swaths of Iraq and Syria and has been pushing into Iraqi Kurdistan. The Islamic Republic, the Shia jihadist regime that rules Iran, supports the Assad regime in Damascus, Hezbollah in Lebanon and Hamas in Gaza.
When our enemies are fighting each other, it's tempting to conclude that our best option is to stay out of the way, but that would be a strategic blunder. It also would be immoral.
Wars can wear armies out. Wars also can transform armies into battle-hardened machines. Should the Islamic State consolidate and expand the territories under its control, it will have the means to threaten the United States and its allies in ways Osama bin Laden never dreamed of.
On the other hand, a tactical alliance with Iran against the Islamic State would last only until Supreme Leader Ali Khamenei achieved his immediate hegemonic goals, to the detriment of those in the region who have aligned themselves with the United States, including Saudi Arabia, the United Arab Emirates, Jordan, Egypt and Israel.
It bears repeating: The motto of the Iranian Islamic Revolution is "Death to America!" With Ayatollah Khamenei's envoys now apparently outsmarting President Obama's diplomats at the negotiating table, it may not be long before the supreme leader possesses both nuclear weapons and the missiles to deliver them anywhere in the world.
That, in a nutshell, is the strategic calculation. The moral case: Yazidis, Christians, Kurds and Jews are among the minorities that have lived in the Middle East for thousands of years and who now face genocidal threats.
Not long ago, those of us who warned of the gathering storm of "Islamism" and "jihadism" — the politically correct term was "violent extremism" — were derided as hysterics or worse.
What's more, according to the Obama administration and much of the foreign-policy establishment, the only serious concern, al Qaeda, was being routed, while Iran, following the election of Hassan Rouhani as president, was being led by "moderates."
Against this backdrop, it is encouraging to read Jeffrey Goldberg's interview of Hillary Clinton in which they discuss "the dangers of jihadism," a topic that has her "hepped-up." Mrs. Clinton said that "the resilience, and expansion, of Islamist terrorism means that the U.S. must develop an 'overarching' strategy to confront it, and she equated this struggle to the one the U.S. waged against Soviet-led communism." (That is what commentators on the right — and a few on the left, e.g., Paul Berman — have been arguing for years, but never mind.)
A central pillar of America's strategy during the Cold War was to support allies willing to fight common enemies. Should we be doing that in the current era as well? Without question.
Start with the Kurds, America's best friends in the Muslim world. They have long been asking for advanced weaponry. Washington has long been turning them down. Ironically, the Islamic State now has such arms — taken from Iraq's military, which went into a swoon after the precipitous total withdrawal of U.S. forces in 2011.
Mr. Obama has begun to assist the Kurds who, among other things, are doing their best to shelter Yazidis and Christians. However, the Kurds "desperately need more coordinated assistance," as Kurdish Regional Government President Masoud Barzani wrote on Monday. They're not asking for "boots on the ground," just increased air support and military equipment. They should get it — as much as is required.
Egyptians also are fighting jihadists, mainly in the Sinai, the peninsula that Israel conquered in a defensive war in 1967 and returned to Egypt in exchange for a peace treaty signed in 1979. Many smart people denounced the coup that overthrew an elected Muslim Brotherhood government in 2013 either because they thought the Brothers should be given more time to demonstrate their incompetence, or because they believed regime change at the ballot box, rather than at gunpoint, would set a much-needed precedent in the Arab world. Such arguments are now moot. Stemming the Islamist tide must be the priority.
Israelis are fighting jihadis, too, in particular Hamas, whose intentions — stated plainly in its charter — are every bit as genocidal as those of the Islamic State and the Islamic Republic. Israelis can and do defend themselves. For that, they should be applauded and supported, not vilified and discouraged.
An "overarching strategy" aimed at defeating jihadism will require more than the utilization of those who are with us to fight those who are against us. Among the additional components: serious defense policies (no, now is not a good time to shrink the military and halt the development of missile-defense systems), energy policies (funding our enemies indefinitely is a really bad idea), immigration policies (can we not at least control our borders and screen out those who hate us?), and a war of ideas (jihadism is about ideology, not grievances).
"One of the reasons why I worry about what's happening in the Middle East right now is because of the breakout capacity of jihadist groups that can affect Europe, can affect the United States," Mrs. Clinton said. "Jihadist groups are governing territory. They will never stay there, though. They are driven to expand. Their raison d'etre is to be against the West, against the crusaders, against the fill-in-the-blank — and we all fit into one of these categories. How do we try to contain that? I'm thinking a lot about containment, deterrence and defeat."
It would have been better had she — and the president she served — thought "a lot" about these questions years ago. Given the dilemmas, challenges and threats facing America and its allies, perhaps we should be thankful for small mercies.