Our enemies are watching this very carefully.
this thread is too long so just in case this isn’t posted (and apologies if it already is)
http://www.suntimes.com/news/nation/343354,vatech041607.articleprint
The 24-year-old man arrived in San Francisco on United Airlines on Aug. 7 on a visa issued in Shanghai, the source said. Investigators have not linked him to any terrorist groups, the source said.
I am willing to predict this will happen again soon as since it was a successful attack the terrorists will probably make it part of their teachings.