Yes, contrary to the administrations belief.
“ISIL is not going to pose an existential threat to us,”
"We have hardened our defenses, our homeland has never been more protected by more effective intelligence and law enforcement professionals at every level than they are now.”
Barack Obama
Ironically both statements are probably true. And a lot has to do with post 9/11 measures the previous administration put in place. Yet still there are security gaps and flaws, human error etc. Since this attack I have seen at least 3 errors or things that were missed that could have prevented it. Mr and Mrs Shitstain were on this path for several years.