Please tell me since when

[BayouBengal07]

America had a mission to "rid the world of evil and free the world"?

Watching Bush's speech on TV right now, I see he mentions how Afghanistan and Iraq are growing into free societies and that America's cause is that of freedom and whatnot.

But since when was America charged with this mission? I mean yeah, we've supported "wars of liberation"...when an international incident broke out that threatened liberty, like when Germany invaded the rest of Europe, or when North Korea invaded South Korea, or when North Vietnam invaded South Vietnam, when Iraq invaded Kuwait, or when Serbia invaded the Kosovo province.

But since when do we start seemingly random wars of liberation, a la Iraq? Why, in the middle of this great campaign against terrorism, do we decide to liberate a country for the hell of it? The security issue, depending who you talk to, is debatable, but the administration sticks by its "liberation" mission, but to what purpose?