Why wasn't Al Qaeda taken seriously before the 9-11 attacks?

the decreasing neutrality of the u. s. in world war i

hope this : )

a system of cooperative federalism emerged, as the powers of the federal government expanded.

well we know that it was fought between america and the united kingdom based on that i assume people consider the second war of independence because brtiain and england (uk)   the uk is made up of england and i assume thats why it was considered that