Every day, hundreds of American citizens shoot each other with legal and easy-to-obtain firearms.
That is the actual ongoing American tragedy. Americans are killing each other prolifically and  efficiently without any assistance required from Libya, Syria, Iran, etc.

More Americans have been murdered in Chicago than combined American military deaths in Afghanistan and Iraq combined.

Want to protect the American people? Forget Immigration bans. Enact the reasonable gun control most other first world countries have.