Bravo to the Brits for breaking up this plot.

British authorities said today they had disrupted a "major terrorist plot" to blow up passenger flights between the United Kingdom and the United States, prompting a security clampdown at British and U.S. international airports and a cascade of delays in trans-Atlantic flights generally.

London's Deputy Police Commissioner Paul Stephenson said 21 people had been arrested in London and in Birmingham England after a months-long investigation into what he said was a plan for "mass murder on an unimaginable scale." He did not say why the announcement was made today.

That seems like a bit of hyperbole to me -- after all, we can all imagine mass murder on a pretty big scale after 9/11. The plot here seems to have involved bringing down AT LEAST 10 aircraft, and as many as 50 people may have been involved.

The result has already been a disruption of trans-Atlantic air service that is only a fraction of what we would have seen if the plot had succeeded.

U.S. officials raised the "threat level" for air transport to red, the highest alert.

Passengers at Dulles airport in Washington and New York's John F. Kennedy Airport were told to expect intensified searches, considerable delays and new restrictions on carry-on items, with particular attention to liquids of all types, especially liquids with a gel-like consistency.

Medicines and baby formula was permitted but at airports in Britain, passengers were being asked to taste these liquids in the presence of security guards.

American Airlines canceled six Thursday flights between the United States and London to accommodate the delays at Heathrow airport, spokesman John Hotard told wire services.

American held three London-bound morning flights, one each from Chicago, Boston and New York's John F. Kennedy International Airport. To balance those cancellations, the airline also dropped three afternoon or evening flights scheduled to travel from London to those U.S. cities, Hotard said.

The British response has been even more stringent.

London's Heathrow airport, the busiest airport in Europe, was closed to most European flights Thursday morning after officials raised Britain's national security alert to its highest level -- suggesting a terrorist attack may imminent. Huge crowds formed at security barriers.

Homeland Security has responded by banning even more common items from aircraft.

" Due to the nature of the threat revealed by this investigation, we are prohibiting any liquids, including beverages, hair gels, and lotions from being carried on the airplane. This determination will be constantly evaluated and updated when circumstances warrant. These changes will take effect at 4:00 AM local time across the country. Travelers should also anticipate additional security measures within the airport and at screening checkpoints.

"These measures will continue to assure that our aviation system remains safe and secure. Travelers should go about their plans confidently, while maintaining vigilance in their surroundings and exercising patience with screening and security officials.

It appears that Muslims are still permitted on aircraft, however, despite their known connection with terrorist plots -- including this one.

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