Scotland Yard revealed that three of the July 7 London bombers rehearsed their attack on June 28, nine days before they launched the real attack that killed 52 innocent people and wounded more than 700, maiming many of them. Three of them are shown on June 28 in this surveillance photo as they rode the Tube for four hours, perfecting their plot. Seen here is the leader, Mohammad Sidique Khan, and his followers, Shehzad Tanweer and Germaine Lindsay. The fourth bomber, Hasib Hussain, was not to be seen on this dry run. They rode the same route that they would take during the attack.

Scotland Yard also confirmed that the Tube bombs used home-made explosives, made in a "bomb factory" in a house in Leeds, and were carried to the target area in coolers until they were ready to be used. The explosive was peroxide-based HMTP, or hexamethylene triperoxide diamine peroxide, which is unstable and degrades quickly at room temperature. Peter Clarke, head of London's Metropolitan Police anti-terrorist branch, said that the bombs had been "effectively made" and that whoever made them had "done some good research and had been well trained."

The four bombs were intended to form a "burning cross", but the fourth bomb carried by Hasib Hussain could not be planted according to the plan when northbound subway services were suspended. Hussain tried to call his dead buddies a few times and then boarded a bus instead, where he detonated his bomb.

A suicide video by the leader of the plot, Mohammad Sidique Khan, was released in which he declared,

"But our words have no impact upon you, therefore I'm going to talk to you in a language that you understand. Our words are dead until we give them life with our blood. ... I and thousands like me are forsaking everything for what we believe. Our driving motivation doesn't come from tangible commodities that this world has to offer. Our religion is Islam, obedience to the one true God, Allah and follow in the footsteps of the final prophet and messenger Muhammad. This is how our ethical stances are dictated. Your democratically elected governments perpetuate atrocities against my people and your support of them makes you responsible, just as I am directly responsible for protecting and avenging my Muslim brothers and sisters. Until we feel security, you'll be our target."

In fact, Khan and his group voiced no public grievances. Violence was their first resort. The ethical stance of radical Muslims such as Khan is that the Koran endorses the murder of infidels until the whole world is Muslim.

There is nothing about these attacks that can not be employed in the subways of New York City or Washington, DC.