Terror Attack Attempts Against US At All Time High

The number of attempted terror attacks against the US are at an all time high.

Just weeks after the failed car bombing of New York's Times Square, the Department of Homeland Security says "the number and pace of attempted attacks against the United States over the past nine months have surpassed the number of attempts during any other previous one-year period."

That grim assessment is contained in an unclassified DHS intelligence memo prepared for various law enforcement groups, which says terror groups are expected to try attacks inside the United States with "increased frequency."

CNN obtained a copy of the document, dated May 21, which goes on to warn, "we have to operate under the premise that other operatives are in the country and could advance plotting with little or no warning."

The intelligence note says recent attempted terror attacks have used operatives and tactics which made the plots hard to detect.

The document specifically mentions the cases of Afghan national Najibullah Zazi, who pleaded guilty in February to plotting attacks on New York's subways, and Times Square bombing suspect Faisal Shahzad, a Pakistani-American.

The intelligence report says both men spent significant time in the United States and were familiar with their alleged targets. Furthermore, the plots involved materials that can be commonly purchased in America without causing suspicion.

The document also says Shahzad and Zazi had short periods of training overseas "compared to lengthier training cycles for earlier operations, reducing our ability to detect their activities."

Many of these plots involve US citizens or legal immigrants who went overseas to receive terror training in places like Pakistan or Yemen and/or received funding from overseas but may or may not have been part of an official terror group like al Qaeda. Rather, they are lone wolf or affiliated terrorists who do not have direct ties to terror groups.

This makes the intel operations to detect and thwart such attacks all the more difficult. In the case of Shahzad, it was only a bomb that failed to properly detonate that prevented the loss of life. The short training cycles means that the terrorists might not have the training necessary to complete their missions, but it makes detection even more difficult.

It also points to the possibility of exposing the terror training camps because more people are flowing through in shorter time, but it also means that tracking those individuals becomes more difficult.

National security relies on gathering intel and thwarting attacks before they reach US shores. That means carrying out clandestine operations to track and eliminate terror training camps and the terror masters in the Middle East and places like Pakistan - the very sort of operation approved by Gen. David Petraeus (and published by the NY Times), which undermines the ability of such clandestine operations to be successful.