Yes. Regardless of whether you support or feel strongly antagonistic towards ISIL, its mandate is quite clear. They wish to create a new Caliphate or Islamist Theocracy in the Middle East. They have made it clear that the current borders of the Middle East are not acceptable to them and that all "Islamic lands" should be under their authority. They have already specifically mentioned that they are interested in overthrowing the Kingdom of Jordan and the Republic of Lebanon once they defeat the governments of Iraq and Syria. ISIL is about strongly altering the status quo, which makes them a source of instability in the region.
Some people say smoking should be banned because it is a serious threat to human health.
The greatest threat to the stability of the slave families is that the family members were separated from the rest.
It depends on which states you are talking about. Tornadoes are a serious threat in the Midwest and South, but less so in other states.
It was very serious
Yes it is
Yes.
yes there can be
No. People are.
because..
yes, it can be
farts
Aspergillosis can be a serious, potentially deadly threat