The F.B.I. has increased its surveillance inside the United States in response to concerns that a military strike against the government of President Bashar al-Assad could lead to terrorist attacks here or against American allies and interests abroad. http://www.nytimes.com/2013/09/01/us/fbi-sharpens-scrutiny-of-syrians-in-us-for-signs-of-retaliation.html?ref=us    The authorities are particularly concerned because Iran — one of Mr. Assad’s closest allies — […]