Homeland Security Secretary Janet Napolitano has taken much of the criticism about the U.S. government's failure to stop the bomber bound for Detroit.

But the vitriol is misplaced. None of the responsibility for keeping the attempted killer off the plane rests with Homeland Security. On the contrary, the many obstacles Congress and both the Bush and Obama administrations have thrown in front of the department kept it from playing a more proactive role in safeguarding the homeland.

Napolitano walked into harm's way when she toured the Sunday talk shows as the "face" of the administration's response. Her statement that "the system worked" proved to be the media equivalent of having a "kick me" sign taped to her back. What Napolitano was actually referring to was the department's system for alerting international flights worldwide in the wake of a threat. That system did work like a charm.

Beyond media gaffes, when the dots started to get connected it was pretty clear that Umar Farouk Abdulmutallab should have been stopped before he bought his ticket, let alone before he boarded a plane. None of the layers of security between him and us, however, were controlled by the Department of Homeland Security.

That starts with the screening before boarding. There was adequate security at Amsterdam to find the bomb. A simple pat down in secondary screening would have done it. That screening, however, is done by the Dutch — not the Transportation Security Administration (an agency under Homeland Security).

The decision to flag an individual for secondary screening or bar him from flying altogether comes from the Terrorist Watch and No-Fly lists. These lists are not controlled or managed by DHS. By law, Congress insisted the airlines — not TSA — do the screening.

Next, Abdulmutallab shouldn't have been given a visa or, if he already had one, it should have been revoked. Yet Homeland Security has almost no authority to address this problem.

Visas are issued by the State Department.

Finally and most important, intelligence agencies and international cooperation with key allies (such as Britain) should have discovered and stopped the plot, as they did with the 2006 London-based liquid-bomb plot. That didn't happen this time.

From the start, Homeland Security has been treated like the weak sister of the intelligence and counterterrorism community. Washington hasn't done much to address that either.

The best way to stop terrorist attacks is to block them before they start. That's a better answer than striking out at DHS or dumping more money into wasteful programs that try to "child-proof" America against every potential terrorist attack.

Congress could start taking the department seriously by consolidating oversight from many dozens of committees and subcommittees to something more streamlined (such as the oversight structure for the Defense Department). Or lawmakers could just keep shooting the messenger.