Tempmaona, what makes me think that is the actual situation that occurred with the San Bernardino terrorists attack in December 2015 in which 14 people were killed by Syed Rizwan Farook and his wife, Tashfeen Malik.  Farook first met her online and had one in-person meeting before petitioning to bring her to the U.S. to get married. She entered under the K-1 visa program for fiancés. Was she properly vetted? The State Department said she was thoroughly vetted and asked such questions as "Do you seek to engage in terrorist activity?" and "Are you a member of a terrorist organization?"  No terrorist worth his or her salt would answer yes.  Farook was able to bring in a fiancé who he married and together committed a horrendous terrorist attack.  It is naïve to believe that other terrorists can’t do it.