LONDON (Reuters) - If it was Islamist militants who struck out of the blue in Madrid last week, then it will dash hopes that Western security forces had blunted the threat from al Qaeda since September 11 and all Europe is at risk.

Despite billions of dollars spent tracking Islamic radicals over the past 30 months, despite destroying their Afghan bases and putting thousands of agents on the streets, Western spies heard not a trace of "chatter" from Muslim militants before the bombers killed 200 rail commuters, security analysts said.

While responsibility remained unclear on Sunday for the worst ever guerrilla attack on a European city, a claim from a purported al Qaeda ally and the arrests of three Arabs caused Spain to play down early accusations against Basque separatists.

The broader implication, experts say, is that security is still worse -- perhaps far worse -- than policymakers feared, even in countries like Spain with experience of dealing robustly with political violence and which were well aware their support for U.S. policy in Afghanistan and Iraq had made them targets.

Jeff Jarvis observes: " In any case, it's a damned shame that terrorists can have an impact on the election and can help bring in the side they apparently wanted."

Eric Olsen has more thoughts on what is, I'm afraid, a bad day for the forces of civilization.

UPDATE: Roger Simon:

I walk out on my deck, looking across the Hollywood Hills at Runyon Canyon, but my mind is in Madrid, at its splendid Puerta del Sol where I have spent so many wonderful days and where sadly fascists have walked before and for too long. But this time they are not under the flag of Generalissimo Franco. This time, ironically, they rally behind the words of a man, Osama bin Laden, whom El Caudillo would have reviled. But of course the cry of both men is the same: Viva la muerte!

Indeed. Meanwhile Mark Aveyard notes a contradiction: "Remember being told by the left that Saddam's regime and Al Queda had no relationship, that they actually hated each other? Now they're saying that Al Queda attacked Spain because the US ousted Saddam!"

And Eric Kolchinsky emails: "Al Queda (or any other terror organization) will rightly perceive that they can influence elections through violence. This vote has greatly increased the probability of a pre-election attack -- here and in Europe." Yes. And it's reduced the likelihood of addressing this problem without major bloodshed. The Spanish electorate has made what seems to me to be a very shortsighted and cowardly decision, and the world may suffer as a result.