At any other time, that might have been a serious threat.
If there were a serious threat, she would have taken action by now.
Probably not close enough be a serious threat at Atlanta in 1996.
Which sounds like they could be a serious threat to movie making.
If they can keep this team together, they'll be a serious threat in two years' time, never mind four.
What I'm actually saying is, they are a very serious threat.
MI5 has rather more serious potential threats to deal with.
They must be pretty sure I know, or have something that's a serious threat to them.
I do not believe that we can continue to stand back in the face of this very serious threat to their lives.
War is also far and away the most serious threat to the environment.