Was it an attempted diversion?

There was a hostage taking at a synagogue in Texas. The hostage taker a known criminal/terrorist was from England. In the end all the hostages escaped and the terrorist was killed. A few interesting questions. Why was said criminal terrorist allowed into the US? Was he on a 'no fly list'? Why the FBI handle this and not local police? Why did the FBI break protocol and kill the hostage taker after all the hostages escaped? Was this an attempt to bolster Blundering Biden's street cred? If so it was pretty pathetic and experts who trained the swat team all say the ending was all wrong. No need to kill the man if there was no immanent danger to anyone.