from an article in the Washington Post:

Many of the organizers confess that they were stunned by the size and scope of the demonstrations two weeks ago. "A big part of our meeting was about digesting the shock of the earthquake that was February 15," said Larry Holmes, an organizer in New York for International ANSWER, one of the U.S. groups organizing the rallies. "We were just as surprised as everyone else. But you're seeing a new sense of confidence among organizations. People don't want this war, and they're giving us a mandate to do whatever it takes to stop it."



The organizers say the February rallies were first agreed upon at a small strategy session in Florence in November. But their roots go back to the days just after Sept. 11, 2001, when activists say they began meeting to map out opposition to what they anticipated would be the U.S. military response to the terrorist attacks on New York and the Pentagon.

In Britain, according to organizer John Rees, several hundred activists first got together the weekend after Sept. 11. Most were from the hard core of the British left -- the Socialist Workers Party, the Campaign for Nuclear Disarmament and the anti-capitalist organization Globalized Resistance, along with Labor Party legislators Jeremy Corbyn and George Galloway. Within weeks, they had combined with representatives from two more important elements -- Britain's growing Muslim community and its militant trade unions. By October they had a name: the Stop the War Coalition.

More than 50,000 demonstrators came out in London for an October 2001 peace rally; the same numbers protested in November against the U.S.-led invasion of Afghanistan. A demonstration last Sept. 28 brought several hundred thousand people to Hyde Park in London to protest war in Iraq and demand "Freedom for Palestine." After that, activists decided to push for a worldwide demonstration.



So, they began organizing within days of Sept 11th. Groups like International ANSWER, Socialist Workers Party, the Campaign for Nuclear Disarmament and the anti-capitalist organization Globalized Resistance come across as far more anti-American than anti-war.