Washington (CNN) – For the first time in nearly four years, a majority of Americans think that a terrorist attack is likely to occur somewhere in the United States in the next few weeks, according to a new national poll.

But a CNN/Opinion Research Corporation survey released Friday morning indicates only one in 20 Americans think that terrorism is the most important problem facing the country today.

Fifty-five percent of people questioned say an act of terrorism in the U.S. over the next few weeks is likely, up 21 points from last August. Forty-three percent said such an attack is not likely, down 21 points from August.

Full results (pdf)

"Eight in ten Americans don't think that a terrorist attack is likely in their community, but the 17 percent who do worry about being targeted by terrorists is the highest that number has been since 2002," says CNN Polling Director Keating Holland. "Nonetheless, terrorism ranks dead last when Americans are asked to name the country's most important problem."

The economy, at 45 percent, tops the list, with the deficit, at 12 percent, and health care, at 11 percent, the only other issues in double digits. Only four percent of those questioned in the poll say terrorism is the country's top issue.

The survey's release comes one day after the Obama administration released its first National Security Strategy, a 52-page outline of the president's strategic approach and priorities on battling terrorism.

The NSS, required by Congress of every administration to be prepared every four years, for the first time combines homeland security and national security, focusing not only on threats internationally but on the threat of home-grown radicals inspired and recruited by al Qaeda.

The CNN/Opinion Research Corporation poll was conducted May 21-23, with 1,023 adult Americans questioned by telephone. The survey's overall sampling error is plus or minus three percentage points.