Joe Glenton argues that Western policymakers may be crying "jihadi" in Mali, but they're secretly worried about China too:
Mali and the other former French colonies which surround it have had extensive dealings with China. The country, one of the poorest in the world, has received substantial Chinese money for development. In 2011 China made good on a package of hundreds of millions, partially as a “gift” to improve the “living standards of Malian people”.
Some argue that China will sit back and let the French do its work for it by handling the crisis and restoring some kind of stability, with China perhaps moving back in later. Contrary to that view, it is worth considering that the intervention may be at least partially informed by a need to counter the Chinese, certainly on the part of the US and also on the part of major European countries.
For what it's worth, I don't doubt that prior U.S. and Western investment in Mali and other African nations had at least half an eye on China's rising influence there (China is said to have 2,000 citizens and roughly 20 firms operating in Mali), but that would hardly be a sufficient condition to motivate such a hasty intervention.
Moreover, I honestly cannot imagine Western policymakers would be so naive -- and historically ignorant -- to believe that a military campaign would foreclose the possibility of restored Chinese influence in Mali after the war. It didn't happen in Iraq or Afghanistan, where China was able to swoop in and scoop up resource contracts when the dust had partially settled. It's more likely that the West is acting against a perceived urgent threat and that the longer-term strategic implications with respect to China are pretty far on the back-burner.