Mitigating Mumbai.
Stratfor has long held that the United States and Europe are vulnerable to armed attacks against soft targets. In an open society, it is impossible to protect everything. Moreover, conducting attacks against soft targets such as hotels or malls can be done with ease, and can prove quite effective at creating carnage.
In fact, as we’ve previously pointed out, Cho Seung Hui killed more people with handguns in his attack at Virginia Tech than Jemaah Islamiyah was able to kill in Jakarta, Indonesia, in the August 2003 bombing of the Marriott Hotel and the September 2004 bombing of the Australian Embassy combined. Clearly, armed assaults pose a threat.
Honestly, couldn't speak for the U.S., but I'm not as confident about the average european cop marksmanship and gun handling skills as STRATFOR is.