“Bana is very weak,” her mom told me.

Russia and Syria appear to be deliberately targeting civilians like Bana. The aim seems to be to bomb and starve civilians into exhaustion and submission, so that they flee or no longer support the opposition, or else support extremists regarded as better fighters. That would bolster the Syrian government narrative that the opposition consists of terrorists who must be fought.

For those of us who generally admire President Obama as a man of principle, it is wrenching to watch his paralysis. As I see it, Syria has been his worst mistake, a huge blot on his legacy.

We can’t be sure that more robust strategies advocated by Hillary Clinton, David Petraeus, John Kerry and others would have succeeded, but Obama’s approach has manifestly failed — and after five years, it should be time to reconsider strategy.

Some of you are thinking: This is horrific, but what can the West possibly do? In a previous column, I quoted a former vice chairman of the Joint Chiefs of Staff, James Cartwright, about the “many things we can be doing now” in Syria. Charles Lister, author of a recent book on Syria, has written a detailed nine-page plan of action for the U.S. I’ve suggested cratering Syrian military runways with missiles fired from Turkey so that Syrian military aircraft can’t take off (Turkish officials have told me that they would go along with this).

Of course, we shouldn’t dispatch ground troops. But if we had cratered Syrian runways several years ago, as many suggested, the horrors of barrel bombing would have been reduced.