Anne-Marie Slaughter writes: For the last two years, many people in the foreign policy community, myself included, have argued repeatedly for the use of force in Syria — to no avail. We have been pilloried as warmongers and targeted, by none other than President Obama, as people who do not understand that force is not the solution to every question. A wiser course, he argued at West Point, is to use force only in defense of America’s vital interests.

Suddenly, however, in the space of a week, the administration has begun considering the use of force in Iraq, including drones, against the Islamic State in Iraq and Syria, or ISIS, which has been occupying city after city and moving ever closer to Baghdad.

The sudden turn of events leaves people like me scratching our heads. Why is the threat of ISIS in Iraq a sufficiently vital interest, but not the rise of ISIS in Syria — and a hideous civil war that has dismembered Syria itself and destabilized Lebanon, Jordan and now Iraq?

I suspect White House officials would advance three reasons.

First, they would say, the fighters in Iraq include members of Al Qaeda. But that ignores recent history. Experts have predicted for over a year that unless we acted in Syria, ISIS would establish an Islamic state in eastern Syria and western Iraq, exactly what we are watching. So why not take them on directly in Syria, where their demise would strengthen the moderate opposition?

Because, the White House might say, of the second reason, the Iraqi government is asking for help. That makes the use of force legitimate under international law, whereas in Syria the same government that started the killing, deliberately fanned the flames of civil war, and will not allow humanitarian aid to starving and mortally ill civilians, objects to the use of force against it.

But here the law sets the interests of the Iraqi government against those of its people. It allows us to help a government that has repeatedly violated power-sharing agreements in ways that have driven Sunni support for ISIS. And from a strategic point of view, it is a government that is deeply in Iran’s pocket — to the extent, as Fareed Zakaria reported in his Washington Post column last week, that Prime Minister Nuri Kamal al-Maliki would not agree to a residual American force because the Iranians forbade it.

The third reason the White House would give is that America fought a decade-long war in Iraq, at a terrible cost. We overturned a stable, strong but brutal government, although far less brutal than President Bashar al-Assad’s has proved to be, and left a weak and unstable government. We cannot allow our soldiers to have fought in vain, the argument goes, so we should now prop up the government we left in place.

This is where the White House is most blind. It sees the world on two planes: the humanitarian world of individual suffering, where no matter how heart-rending the pictures and how horrific the crimes, American vital interests are not engaged because it is just people; and the strategic world of government interests, where what matters is the chess game of one leader against another, and stopping both state and nonstate actors who are able to harm the United States.

In fact, the two planes are inextricably linked. When a government begins to massacre its own citizens, with chemical weapons, barrel bombs and starvation, as Syria’s continues to do, it must be stopped. If it is not stopped, violence, displacement and fanaticism will flourish.

Deciding that the Syrian government, as bad as it is, was still better than the alternative of ISIS profoundly missed the point. As long as we allow the Syrian government to continue perpetrating the worst campaign of crimes against humanity since Rwanda, support for ISIS will continue. As long as we choose Prime Minister Maliki over the interests of his citizens, all his citizens, his government can never be safe.

President Obama should be asking the same question in Iraq and Syria. What course of action will be best, in the short and the long term, for the Iraqi and Syrian people?

And in response to that question, many will pose another: what’s best for the American people?

“We can no longer be the world’s policeman” — there’s probably no more widely held view among Americans right now. The world, perpetually inclined to misbehave, can’t expect us to come along and clean up its latest mess.

The conceit and condescension embedded in this view is breathtaking.

William Saletan puts it in slightly more refined terms: “We’ll help you, but only if you clean up your act. Our help is limited, and your initiative is required.”

The world is being told to stop taking advantage of American generosity.

But the mess in Iraq is very much of America’s making. The U.S. government broke up the Baathist state with very little thought about what was going to take its place, so for American commentators to be telling Iraqis to clean up their act, shows that American hubris is still alive and well even among those who concluded the war in Iraq was a mistake.

Anne-Marie Slaughter correctly asks: “What course of action will be best, in the short and the long term, for the Iraqi and Syrian people?”

She advocates the immediate and limited use of military force: “Enough force to remind all parties that we can, from the air, see and retaliate against not only Al Qaeda members, whom our drones track for months, but also any individuals guilty of mass atrocities and crimes against humanity.”

But even if it wants to, can the U.S. retaliate against any individuals guilty of mass atrocities and crimes against humanity? That sounds much easier said than done.

Fred Kaplan who like most American progressives these days believes U.S. foreign policy should be defined in terms of national interest, writes:

It is not in U.S. interests for a well-armed, well-funded jihadist group like the Islamist State of Iraq and Syria to fulfill its self-proclaimed destiny, i.e., to create an Islamist state that spans Iraq and Syria. The question is how to stop this from happening and what role, if any, the United States should play in the stopping.

The New York Times’ Roger Cohen, in an opinion piece headlined “Take Mosul Back,” concludes, “President Obama should use targeted military force to drive back the fanatics of ISIS,” but he doesn’t elaborate. “Targeted military force” — I assume that’s a finessing euphemism for smart bombs and drones. But it’s fantasy to believe that air power alone will “drive back” the ISIS fighters.

That’s right, because the U.S. can’t very well launch so-called surgical strikes against a largely invisible enemy.

The U.S. intelligence Panopticon is stumbling right now. Its ability to see everywhere isn’t matched by its ability to see one place in particular. White House officials are trying to figure out “how to gather useful intelligence about the militants.”

Mass collection and storage of largely useless cellphone metadata turns out to be much easier than tracking the most powerful terrorist organization in the world — even though ISIS has helpfully been publishing annual reports and it has not been shy about using the internet to further its aims as its small army carves up national boundaries.

It’s easy to conclude that since the U.S. had a major hand in creating this mess, since it lacks much influence on the ground, and since through ill-conceived military operations could easily make the situation worse, the only way of doing no harm is to do nothing at all.

The problem is that inaction also has effects.

Over the last three years, Bashar al-Assad has carefully tested the United States and through an empirical process and with Iranian support, created a model of effective tyrannical leadership.

In a gruesome way, his experiment has turned out to be surprisingly successful and thus must now be an appealing option for Nouri al-Maliki to follow. For the Iraqi leader, the fact that his country already got ripped apart by American and British forces, will make it all the more easy to try and use military force to solve his political problems.

Yet as the UN now warns, the Middle East is on the brink of a sectarian war that threatens to suck in the whole region. Such a war will have an impact on the whole world.

Sectarianism is a political disease. It reduces all people to immutable identities that become the basis for political affiliations.

If all that counts is whether you are Shia or Sunni it no longer matters what you think.

Political leaders no longer have to work to win arguments; all they have to do is rally their kin. Everyone is then governed by the politics of us and them.

The Middle East may currently be the epicenter of sectarian division, but we are all at risk of moving down the same politically regressive path.

The only alternative to worsening division is dialogue. A sectarian war is a war that no one can win.

The two powers who most urgently need to talk to each other are Saudi Arabia and Iran and yet each is adopting a tougher position.

The most constructive way in which the U.S. might now intervene would be by bringing together the region’s arch enemies.