Assad kills 10 - 20,000. Bush kills 116,000. What am I missing here?

According to the Iraq Body Count website, between 115 and 116,000 civilians have died in Iraq:

Iraq Body Count (IBC) recorded 4,087 civilian deaths from violence in 2011. Evidence of these deaths was extracted from some 6,828 distinct reports collected from over 90 sources covering 1,884 incidents, each of which is openly listed on the IBC website. This brings the total number of deaths in the IBC database so far to 115,342. These numbers represent a verifiable documentary record of deaths, and are not estimates (for some partially estimated figures, see 'WikiLeaks update' below).

According to the NYT, 

Emboldened by faltering diplomacy and Russia’s pledge to keep supplying weapons, the Assad government in March launched bloody assaults on insurgent strongholds, driving rebels from the cities of Homs and Idlib. According to estimates from the United Nations, the conflict has left more than 10,000 dead, thousands more displaced and as many as 40,000 people may have been detained. The Red Crescent said in May 2012 that as many as 1.5 million people needed help getting food, water or shelter.

Source: Assad death toll.
Source: Bush death toll.
Graphic: Groobiecat