Polls suggest Americans are not isolationists.
The University of Maryland's Steve Kull debunks the myth of rising American isolationism:
Asked what kind of role the US should play in the world only 11% said it should not play any leadership role. If the public was really going through an isolationist phase more would surely have endorsed this view.On the other hand only 14% said the US should be the single world leader. This shows how low the support is for the US playing a hegemonic role.
The option that got the clear majority--endorsed by 70%--was for the US to play "a shared leadership role." Furthermore, this group was asked a follow on question about whether the US be the most active world leader or if it should be "about as active as other leading nations." Most chose the latter option. This has not changed significantly since it was last asked in 2005.
These responses also mirror a question that PIPA and the Chicago Council have asked for some years now. Asked most recently in 2006 what role the US should play in the world only small minorities endorse the isolationist position that that US should "withdraw from most efforts to solve international problems" (12%) or the hegemonic position that the US should "continue to be the preeminent world leader in solving international problems" (10%). A large majority (75%) instead sided with the multilateral position that the "US should do its share in efforts to solve international problems together with other countries."
A recurring theme is that American public tends to look to multilateral institutions, especially the UN as a means for the US to offset its dominant role in the world.
Coming back to the Pew poll there was also strong support for having a strong UN. Eighty-one percent gave "strengthening the United Nations" "top" (37%) or "some" priority (44%) as a foreign policy goal of the US.