The Boston area was home to some of the 9-11 terrorists before they launched their attacks - they walked our streets, lived in our neighborhoods and rehearsed their deadly missions here.

 And as we saw on that day, America's very strength - our technological might - was turned into a weapon of mass destruction used against us.
The death of Osama bin Laden was a major victory in our efforts to bring justice to those who masterminded the 9-11 terrorist attacks, and the Obama administration has dealt additional devastating blows to al-Qaeda in the deaths of some of the network's key lieutenants. We are safer today than we were ten years ago. But the threat is not gone. Al-Qaeda is a Hydra - when one arm is severed, another immediately grows in its place.

America's aviation, chemical and nuclear sectors remain at the top of al-Qaeda and other terrorist target lists. They continue to test our systems, in an effort to identify and exploit loopholes in the protections we have established. Just last week, the FBI issued an alert about potential threats at small airports, and over the summer the Department of Homeland Security warned of attempted sabotage by terrorist insiders that could infiltrate some of our most critical facilities such as refineries or electric utilities.

Whether it is in underwear, in a printer cartridge, in a shipping container or through cyber-attacks designed to shut down our economy, terrorists will continue trying to invent new ways to strike our land and people.

Of the several failures the 9-11 Commission highlighted in its first report on the attacks, the Commission noted, "The most important failure was one of imagination." We simply failed to imagine the diabolical scenario that al-Qaeda devised on 9/11.

It is not sufficient to simply act to prevent the same attacks we experienced 10 years ago. We must continue to imagine the loopholes that the terrorists of tomorrow will seek to exploit and be vigilant in our efforts to close them. Unfortunately, we have failed to do so in the past decade in some egregious ways.
- Aviation remains at the top of terrorist target lists and aviation systems remain highly vulnerable to attack.

Last August, the Department of Homeland Security was supposed to finish implementing my law that all cargo on passenger planes be screened for bombs. Unfortunately, while the Department has ensured that domestic cargo traveling on passenger planes between Boston and Boca Raton is secured, it has left the international cargo traveling from Bogota to Boston largely unscreened and vulnerable.

We saw as recently as last October with the thwarted Yemen plot that cargo from overseas can be used as a bomb. The Obama administration needs to increase its progress to fully meet the requirement, including mandating 100 percent screening of freight on cargo planes.
- We know that nuclear attacks represent al-Qaeda's Holy Grail.

In 2007, legislation I authored included the requirement that 100 percent of maritime cargo containers must be scanned for nuclear materials before they are loaded onto boats headed for our country. Unfortunately, even though the technology and processes can be put in place to meet this common-sense mandate, both the Bush and the Obama Administration have failed to implement my law.

- A terrorist attack on a chemical facility could wreak devastation for hundreds of miles beyond the point of attack.

Since 2004, I have offered legislation to require the use of cost-effective safer chemicals and processes at chemical facilities. Republicans and the chemical industry have vigorously opposed these efforts, supporting exemptions for thousands of facilities that contain toxic chemicals from having to comply with even the inadequate law on the books. In the last Congress, I successfully led House negotiations on comprehensive chemical security legislation that closed the loopholes and gave the federal government the tools it needed to keep these facilities safe. But the Senate failed to act, and this year, Republicans have proposed extending the loopholes for an additional seven years. This creates unacceptable risks.

- The electric grid's vulnerability to attack is one of the single greatest threats to our national security.

Despite expert warnings, including from the Department of Defense, of vulnerabilities in our grid that could result in widespread blackouts and cause severe threats to our security, economy and health, industry has not responded by fixing its systems. In the last Congress, I led efforts to craft a bipartisan bill, the GRID Act, which provides the federal government the authority to order the needed security upgrades. Last year, the bill passed the House of Representatives overwhelmingly. Now, the electric utility industry is lobbying the Republican majority to weaken its provisions so that industry will remain in charge of deciding what its own security measures need to be.

Since that tragic day 10 years ago, we've considerably enhanced the security of many of our key transportation sectors and critical infrastructure. Nevertheless, we should not be planning for the last attack; we need to be prepared for the next one. Our failures should never again include a failure of imagination. In the past decade, we have been forced to face a new reality. In the future, we must be vigilant and never let a failure of imagination enable terrorists to attack us again.

The above Op-Ed was published in the MetroWest Daily News on September 11, 2011. http://www.metrowestdailynews.com/opinion/x948305324/Markey-We-still-are...