In response to HHDomains post,
The IRA, Basque Seperatists & Tamil Tigers are all internal problems, they only affect the specific countries they are fighting in. America SHOULDN'T intervene if anything as it is none of their business.
This whole "war on terror" thing started in Africa with the bombings of the American embassy's in Kenya and Tanzania. These were performed by al-qaeda. The US however did not act and let al-qaeda grow in strength in terms of arms, members and politically also.
The largest Islamic population in the world is found in Indonesia, yet you do not see as much US activity there, where al-qaeda is a lot more potent, compared to the middle-east. The US is starting to look at the horn of africa, in particular Somalia, with a bit of pessimism as the country (which has been lawless and run by warlords practically for the last 10-odd years) is now being overrun by the Union of Islamic Courts,
read more here. It is the largest fighting force in the country, and the government, which holds no REAL power looks like it's next target. Ethiopia has "unofficially" sent troops into the borders of Somalia as a deterant, they'd rather have the bad government and warlords than a country run with a powerfully, actively violent Union. The US's stance sees this as a potential training ground for al-qaeda since there have been claims of links between some of the leaders in the Union and al-qaeda. Has there been any action though, diplomatic or otherwise?
Footnote: The IRA is disarming the last I heard.