VOA常速英语:Terrorism Casts Shadow on Obama's Speech to Congress

WASHINGTON— President Barack Obama is preparing to deliver his annual State of the Union address at a time of heightened vigilance in Washington and beyond following terrorist attacks in France.

The ceremonial pageantry of Tuesday’s presidential speech before a joint session of Congress comes against a backdrop of ramped-up security on both sides of the Atlantic.

In recent days, there have been a shoot-out in Belgium, police raids in Germany, arrests in Greece, and stepped-up security across Europe -- all following the attack on French satirical magazine Charlie Hebdo.

Security efforts must adapt to an evolving threat, said Rob Wainwright, who heads the European Union law enforcement agency Europol.

“We are seeing a very determined response by our national governments, national police authorities, and at institutions like Europol urgently reviewing ways that we can better support counter-terrorist services everywhere, and the better exchange of intelligence, in the tracking of terrorist financing, and illicit firearms, and in particular monitoring terrorist activities online," Wainwright said.

For Obama, who hopes to work with a new Republican-controlled Congress on an agenda that includes domestic priorities, the fast-paced international developments are forcing greater attention to security matters at home and abroad.

“This phenomenon of violent extremism, the ideology, the networks, the capacity to recruit young people, has metastasized and it is widespread, and it has penetrated communities around the world," the president said.

"This is a problem that causes great heartache and tragedy and destruction, but it is one that ultimately we are going to defeat," he added.

With terrorist sleeper cells believed to exist in numerous countries and the possibility of the Charlie Hebdo incident rallying extremists across the globe, the Obama administration and other governments are asking not whether another attack will be attempted, but when and where.