I have been giving a lot of thought lately to the cowardly bombing attacks in London, England in recent weeks. As I understand it, the purpose of terrorism is either to terrorize a group of people into doing what the terrorist organizations want them to do, or to act as a form of retaliation. In the case of the London bombings, it must certainly be the latter. Otherwise, the terrorists that performed the cowardly act of bombing a civilian population must be dumber than a door knob. It is possible that I am wrong, and the terrorists are indeed dumber than a door knob, and that they actually expect these attacks to convince Britian to withdraw from the activities in Iraq and Afghanistan. This is a highly unlikely outcome of the attacks.
In the last 100 years, London has been heavily attacked by Germany in vicious air raids when it was under the rule of Adolph Hitler, and more recently, when the IRA would perform frequent terrorist attacks in London and other cities in England. At none of these times did England even consider surrendering or changing their behaviour during WWII or any time since.
Given this, why would a bunch of cowardly terrorists think that a few bombs on public transit systems would scare the British or the British Government? As both Hitler and the IRA discovered, terrorist type attacks only make the British more resolute in their beliefs and actions.
As has been mentioned in other places, the terrorists have messed with the wrong people. The British may not be known for aggressive behaviour internationally, but they are definitely a country it is better to be a friend of than an enemy of.
My condolences go out to the victims of the recent cowardly attacks and their friends and families. Your friends in North America grieve with you.