How should the world respond to the threat of the islamic state?

Negotiation is the main output. They should join the countries that have been victims of this group and seek solutions through peaceful means. The above is achieved with sufficient commitment. It is a titanic task but not impossible. The largest number of nations in the world must be allied to coordinate actions of a military nature. One can also think of a diplomatic solution to the eventual failure due to possible military action.

answer; people where able to travel across the u.s.a faster than any other mode of transportation,travel time was about a week,from coast to coast

the commander in chief