Assad deserves to lose because he has been a persistent enemy of ours, and is responsible for unleashing al Qaeda suicide bombers and hosting Baathist resistance to kill our troops during the Iraq War. I've long felt that it is also useful to show that if you are an enemy of America, we will eventually take an opportunity to exact revenge.
But if defeating an enemy and setting an example for other potential enemies isn't sufficient, and if you need just absolute evil that doesn't just rely on using chemical weapons on civilians, keep in mind that Assad's thugs can teach al Qaeda a thing or two about brutality:
The UN investigation into the Syrian fighting has found a pattern of deliberate violence against civilians it expected from al Qaeda but was surprised to find such bad behavior was a government policy as well. It was also discovered that a lot of the government atrocities against civilians were carried out by an unofficial but very real government backed Shabiha militia. This group has been around for years and was long part of the government secret police effort to control the population. The investigators have known about Shabiha for several years but as more Assad insiders come forward there is a more accurate picture of how Shabiha operates and who the key players are. The government never acknowledged Shabiha, whose members were often criminals and thugs. But with the civil war a growing number of senior members of the Assad government have defected to the rebels and supplied details on Shabiha. While al Qaeda gets the most publicity for atrocities against civilians the Shabiha has actually been worse, sometimes wiping out entire pro-rebel villages and killing their victims in gruesome ways (slit throats or torture for no particular reason). UN investigators are building a case for war crimes charges against al Qaeda (and other Islamic terrorist groups) and the Assad government.
Yeah, we wouldn't want to support rebels if any of our aid might inadvertently reach jihadi rebels who would use that aid to kill civilians.
Defeating Assad is just the first step of coping with the problem of Assad and a divided country that has become a Shia-Sunni battleground and an Arab-Persian fight as Iran struggles to retain their major foothold in the Arab world. But it must be the first step.
