What the world saw last Thursday evening was an American president torn between personal preferences and cold reality. The result is a US that is once more moving towards greater military involvement in Iraq – but only reluctantly and incrementally.
Describing himself as someone who ran for office "in part to end our war in Iraq and welcome our troops home", Barack Obama announced a policy of dropping supplies to save thousands of members of the Iraqi Yazidi religious minority – and authorised but did not order air strikes on advancing insurgents from the Islamic State of Iraq and the Levant (known as Isis).
He deployed humanitarian terms ("to prevent a potential act of genocide") as well as self-interest ("to protect our American personnel"). Conspicuously absent was any strategic rationale, and longer-term plan, for US action.
The announced policy may provide relief to the Yazidis desperate for food and water and, with its narrow parameters, to Americans desperate to avoid renewed entanglement in what The New York Times described as "that graveyard of American ambition".
Any such relief will be shortlived given the nature of US interests and the threats against them. Indeed, the first air strikes against Isis positions near the city of Erbil, the Kurdistan Regional Government's capital in northern Iraq, came 12 hours later.
Isis is more of a threat than al-Qaeda, which was and is mostly content to destroy. Isis has an agenda: to create a caliphate based on what it views as a return to pure Islam over swaths of the Middle East and beyond.
It has a growing foothold in Syria and Iraq. At some point it will train its guns on Jordan, Lebanon and others. This would constitute not just a humanitarian but a strategic nightmare in a region whose energy resources remain vital to the world's economy.
What is more, success would feed ambition: it would only be a matter of time before foreign Isis fighters returned home and threatened the security of Europe and the US from within.
It is fantasy to think that the Iraqi government and its military can stop Isis on their own. Isis has zeal and momentum; Iraq is beset by division, corruption and incompetence.
The power struggle among three men – Iraq's president Fouad Massoum; Haider al-Abadi, whom he has designated prime minister; and Nouri al-Maliki, who had held that office since 2006 – both reflects and adds to the country's disarray.
What should be done? The US should carry out sustained attacks on Isis in both Iraq and Syria. The border is irrelevant; what is essential is that Isis is slowed and weakened.
Economic and especially military aid to the Kurds holding the line against Isis should be increased and sped up. It is pointless to object that this will weaken the integrity of Iraq. That horse has left the barn. Kurdish independence is a reality that needs to be accepted. Rump Iraq is largely under the sway of Tehran, not a balance to Iranian power but a vehicle. The goal should be to stop Isis but to do so in a manner that avoids making Iran the beneficiary.
The weakening of Isis in Syria may provide an opening for the regime of Bashar al-Assad to strengthen its position. This would be unfortunate but not as bad as Isis strengthening its position in Syria. That said, the weakening of Isis may offer a chance to bolster (using arms and intelligence) any remaining moderate alternatives to the regime.
It is also time to shore up Jordan, which must prepare to defend itself while struggling under the weight of an enormous refugee burden.
Above all, Mr Obama needs to articulate what the US is doing and why. He must explain why isolationism makes no more sense now than at other times in modern US history.
A course of action along the lines suggested here will not repeat questionable attempts at nation-building. It will not require ground troops. Rather, it will use air power for what it is designed to do: weaken an adversary and force it on to the defensive. Others, including Kurds and Iraqis, will need to provide ground forces.
Mr Obama and those around him might also rethink America's role. They tend to exaggerate the costs and risks of acting, and discount those of inaction.
Yes, the 2003 Iraq war was an ill-advised, poorly executed war of choice. But also ill advised was not pressing harder for US troops to remain; the president described this criticism as "bogus and wrong", but a residual force of 10,000 US military advisers and trainers would have enhanced Iraq's military capacities and damped political infighting.
A bigger error was calling for regime change in Syria then doing little to bring it about. The ensuing civil war, the lack of aid for relatively moderate opponents of the regime, the failure to attack the regime when it used chemical weapons – all created a vacuum exploited by Isis.
The president said people the world over look to America to lead. He is right. Now is one of those times.
This article appears in full on CFR.org by permission of its original publisher. It was originally available here.