The purpose of terrorism is to terrorize: to scare or intimidate a society. The perpetrators of the bombings in London on Thursday may claim to have some lofty purpose, but attacks on ordinary citizens are barbaric, pure and simple. And, once again, the murderers have failed: They have not broken or even bent the will of Londoners or the convened Group of Eight leaders, who, in a sense, were the targets of these attacks. Instead, the perpetrators appeared as cowards and have further discredited themselves and their so-called cause.

While many details are still unknown, this much is certain. Four bombs went off in less than an hour during the Thursday morning rush-hour commute: three on the subway and one on a double-decker bus. British officials say the death toll is certain to climb past 50. Some 700 people have been injured.

A previously unknown Islamist group, The Secret Organization of al-Qaeda Jihad in Europe, claimed responsibility, saying the attacks were "in revenge for the massacres that Britain is committing in Iraq and Afghanistan." The group threatened Italy and Denmark unless they withdrew their troops from Iraq.