U.S. President George Bush says tighter security at American sea ports will make the nation more prosperous and better prepared for possible terrorist attacks.

George Bush speaks before signing the Security and Accountability For Every (SAFE) Port Act in Washington, Oct. 13, 2006

President Bush signed into law a series of security improvements for American sea ports meant to make it more difficult for terrorists to smuggle in a nuclear, chemical or biological weapon.

"Our seaports are a gateway to commerce, a source of opportunity and a provider of jobs," he said. "Our ports could also be a target of a terrorist attack, and we are determined to protect them."

More than 11 million shipping containers clear American ports each year, many without inspection. The new measures fund the development of technology to allow inspectors to check for dangerous materials inside cargo containers, without opening them.

It requires the installation of radiation detection equipment at America's 22 busiest sea ports by the end of next year, and background checks on workers at all of the nation's 361 ports.

The law also expands a partnership with the private sector, rewarding shippers who improve their own security with expedited clearance through customs.

Port of New Orleans

The Port Security Act codifies a four-year-old Container Security Initiative that puts U.S. officials at dozens of foreign ports on five continents inspecting cargo before it is shipped to the United States.

The law also empowers the Department of Homeland Security to establish plans for reacting to a terrorist attack on American sea ports. The president says he wants officials to be ready to reopen ports and waterways as quickly as possible, if they are targets of attack.

"We will do everything we can to prevent an attack," the president said. "But if the terrorists succeed in launching an attack, we will be ready to respond."

The legislation was one of the last bills passed by Congress before next month's congressional elections. It helps the president focus on what he says will be the key to his Republican Party maintaining majorities in the House and Senate: national security and the economy.

Opposition Democrats backed the port security measure, but say it does not address what they say is a shortfall in funding for security improvements on rail and mass transit.