The cyberwar being waged against Israel should be of great concern not only to that country but also to the U.S. and our other allies.

In recent days, a hacker known as oxOmar, supposedly a Saudi teenager, has mounted assaults which have disrupted the websites of the Tel Aviv Stock Exchange and El Al airline. He has also posted online the details of roughly 20,000 Israeli credit cards. That he has been able to cause so much mayhem is notable because, outside the U.S., Israel might be the most advanced user of computers and Internet in the world. Yet Israeli computer scientists–some of the best in the world–have not been able to stop these brazen assaults.

Would we do any better? The answer is no, according to Gen. Keith Alexander. He should know: As head of the National Security Agency and Cyber Command, he is our top computer warrior. According to Wired magazine, in a speech last week, Alexander warned that even Defense Department computer networks are “not defensible” and that civilian networks, which control much of the economy, are in even worse shape.

The problem at the Pentagon is that it has too many networks–15,000–a figure Alexander is pushing to consolidate into a more manageable 3,000. Achieving that goal will require overcoming a monumental amount of bureaucratic inertia. But protecting civilian networks, such as the ones targeted in Israel, will be even harder. The NSA and Cyber Command lack the legal authority to monitor civilan networks in real time, which is what it would take to detect and stop attacks. Giving them that authority would require an act of Congress but, given the resistance to such a move that inevitably would be heard from the computer industry and libertarian lobby, that is not likely to happen anytime soon. It may well take a cyber Pearl Harbor before we start to seriously protect our civilian computer infrastructure. That’s a sobering thought as we watch a close ally grapple with its own cyber attacks.