how does this end?

The Wall Street Journal has a good roundup of various and conflicting views on what to do about the so-called Islamic State. Perhaps the most significant passage is this:

For military planners, destroying the terrorist group’s headquarters and crippling its fighting force is a relatively simple assignment, say strategists: It would require some 40,000 troops, air support and two months of fighting.

The problem is what do to after taking responsibility for won territory. With the recent experience of Afghanistan and Iraq, that is a job no Western leader wants.

There are of course military measures that could kill many of the ISIL fighters and lay waste to the territory they now hold. That is the easy part. The hard part, and the part that matters, is what happens next.

The American-led coalition took down Saddam Hussein's government but failed to replace it with an effective and sustainable regime. We did not want to "occupy" Iraq, and the successor government was unable to unify the nation. Iraq remains divided by ethnic, tribal, regional, and sectarian differences. There are unresolved disputes over the division of oil revenues and the degree of local autonomy for the Kurds.

Similarly with the suggested anti-ISIL coalition. Destroying ISIL is every member's secondary goal. The Turks care more about fighting Kurds. The Russians care more about keeping Assad in power. The Iranians care more about maintaining their links to Hezbollah in Lebanon and strengthening their influence in Iraq. The French care more about demonstrating their great power status and reducing the flow of migrants into Europe. And, truth be told, we Americans care more about ending viral videos of beheadings and standing up to Iran and Russia than building a new entity where ISIL now reigns.

The many critics ritually say, "We need a strategy." Any good strategy has to deal with more than the destruction of ISIL and offer an acceptable and achievable way for things to end up.