worst case scenario

I do not know who planted the bombs in London. Neither does anyone else (except the people who planted them). Even if we devote vast amounts of money to the topic, we may never know. Remember the Weapons of Mass Destruction fiasco? Intelligence can be wrong.

All we know for sure is that two groups will gain from the bombings. First, anyone who wants publicity. The media gives maximum publicity to anyone who can kill another person in a dramatic way. There is no doubt that crazy individuals have used bombs in the past, so this option needs no further comment. Given that there is an infinite supply of crazy individuals, this must be the most likely cause.

And the worst case scenario? The second group who benefits is any government that wants more power over its people. And freedom to invade other countries, spend less money on Africa, more money on defense, etc. Governments routinely spend billions creating weapons, and using those weapons to kill people in wars. They routinely calculate that killing certain people is in the long term interests of the country. Heck, every time they approve a budget for the health service, they gamble with lives - "if we did this, X people would die, but if we did that, then Y people would die." Like it or not, governments make decisions that result in the deaths of some of their own citizens, so that the biggest overall number can survive. It is a good thing they do.

Would a politician make a similar calculation regarding bombs? No - it is unthinkable. But there are secret parts of the system for whom the unthinkable is their daily work. But surely we can trust them, right? Well remember the Weapons of Mass Destruction (gulf war 2). And the babies thrown out of incubators (gulf war 1). And the Tripoli radio transmitter (that prompted the bombing of Libya). Etc., etc. The first casualty of war is truth. The second casualty is human lives.

Remember the Lavon affair.