WASHINGTON (Reuters) - U.S. authorities are having a harder time detecting terrorism threats on American soil, top officials said on Wednesday, more than nine years after the September 11 attacks thrust the United States into a global struggle with Islamist militancy.
The officials, including Homeland Security Secretary Janet Napolitano and FBI Director Robert Mueller, told a Senate panel that al Qaeda and its affiliates have shifted over the past year to plotting smaller-scale attacks, such as shootings and car bombings, that can be carried out inside the United States with greater frequency and against a broader range of targets.
The danger of homegrown militancy has also spiked, with efforts through English-language propaganda to recruit American operatives capable of penetrating the U.S. security cordon.
“These elements, which make the terrorist threat more diffuse, also make it more difficult for law enforcement or the intelligence community to detect and disrupt,” Napolitano said at a hearing before the Senate Committee on Homeland Security and Government Affairs.
The sobering assessments come at a time when U.S. authorities have been criticized after being caught off-guard by a failed attack on Times Square in May and the attempted bombing of a Detroit-bound airliner last December.
“Increasingly, we can see ... that our enemies in the war with Islamist extremism are bringing the fight to the homeland in the United States with greater frequency,” said Sen. Joseph Lieberman of Connecticut, an independent who chairs the panel.
The September 11 attacks on New York and Washington killed about 3,000 people in 2001, prompting U.S. officials to fear al Qaeda was plotting other mass casualty events, possibly including the detonation of a nuclear device.
Officials said the central branch of al Qaeda that carried out the attacks is now at its weakest point since 2001 due to joint U.S.-Pakistani counterterrorism efforts along Pakistan’s border with Afghanistan.
But Mueller told lawmakers that al Qaeda affiliates in Pakistan, Afghanistan, Yemen, Somalia and Iraq now pose a growing threat to the United States.
The list includes the Pakistani Taliban, the Haqqani network and other groups that have been involved in cross-border attacks on U.S. forces in Afghanistan.
As a result, Napolitano warned that the United States faces increased danger from roadside bombs, as well as small arm attacks of the kind used to devastating effect in the 2008 Mumbai rampage that killed 166 people in India.
The list of potential targets now includes hotels, sports stadiums and other public areas as well as famous landmarks, airliners, chemical plants and ports.
Underpinning U.S. concerns is a rise of homegrown militants including about two-dozen U.S. citizens who have trained with Islamist militants in Somalia. Officials said U.S. citizens have also assumed a growing number of leadership positions within militant networks, including radical imam Anwar al-Alawki, an al Qaeda militant in Yemen.
About 20 U.S. citizens and resident aliens aligned with violent Islamist extremists have been arrested or convicted of terrorism this year in the United States and elsewhere, vs. 43 in 2009.
“While it is not clear if this represents an actual increase in violent radicalization ... it is nonetheless evident that over the past 12 months efforts by violent extremist groups and movements to communicate with and recruit individuals within the United States have intensified,” Napolitano said in her testimony.
Additional reporting by Jeremy Pelofsky; Editing by Jerry Norton