In some ways, the Syrian regime's latest tool of terror, barrel bombs, are nothing special. The oil drums filled with explosives and metal shrapnel such as nails and then dropped on rebel-controlled areas differ from conventional bombs mostly in that they're cruder. It's not clear that barrel bombs are any more lethal or destructive than conventional bombs, and they may in fact be less so.

An analysis by munitions expert Richard M. Lloyd estimates that barrel bombs are effective only 25 percent of the time, and even then they're so poorly designed that a person standing 40 feet away only has a three percent chance of getting hit. Eliot Higgins, perhaps the foremost observer of weapons use in Syria who is not employed by a major intelligence agency, has decried media hype around the barrel bombs: "It's like calling it a 'barrel bomb' makes it some special extra powerful bomb, when it's basically a piece of crap," he wrote on Twitter.

But there is something legitimately scary about the weapon's do-it-yourself ethos and its new systematic deployment against the neighborhoods of Aleppo. It speaks to the regime's single-minded focus on finding new ways to kill, its narrow and obsessive pursuit of mayhem and destruction as seemingly official strategy in the conflict that has run for nearly three years now.

The barrel bombs are disturbing because they affirm what has been increasingly clear throughout the Syrian war: The Bashar al-Assad regime is interested in no path forward other than by killing, something at which it is sufficiently competent to avoid losing the war, but not perhaps to win outright. It might seem perverse to see the Assad regime's lack of skill at warfare as a downside, but that has helped to turn the conflict that began as popular protests into a stalemate, a long and drawn-out fight that could last another decade. The barrel bombs speak to Assad's inability to win the battle outright, as well as his unwillingness to consider any other strategy than indiscriminate killing, a combination that suggests many more years of horrific conflict in a country that has already seen enough to scar it for a generation.