President Obama says General Clapper is one of the nation's most experienced and most respected intelligence professionals.

"He has improved information-sharing, increased intelligence support to our troops in Afghanistan and Iraq, upheld civil liberties, and he played a key role in our effort to update and reorient our intelligence community to meet the threats of our time," said President Obama.

If approved by the Senate, Clapper would be the fourth Director of National Intelligence. Retired Admiral Dennis Blair resigned last month after a series of conflicts with the White House.

Mr. Obama introduced his nominee Saturday in a brief speech in the White House Rose Garden.

Clapper spoke for only 40 seconds, saying nominees for Director of National Intelligence (DNI) are "better seen than heard."

"We have the largest, most capable intelligence enterprise on the planet, and it is the solemn, sacred trust in the DNI to make that enterprise work," he said.

Clapper has spent several decades in military intelligence. He led the National Geospatial-Intelligence Agency, which analyzes images taken from above. He also headed the Defense Intelligence Agency, which often works closely with the CIA.

Clapper is known for being blunt and direct. His manner has won praise in the military, but some of the lawmakers who will decide whether he is confirmed say he is not cooperative enough.

President Obama says Clapper's no-nonsense style will be an asset in his new job.

"He possesses a quality that I value in all my advisors: a willingness to tell leaders what we need to know, even if it is not what we want to hear," added President Obama.

Mr. Obama admits that coordinating the activities of 16 U.S. spy agencies is a major challenge, but he believes Clapper will be able to do so.

"In short, our intelligence community needs to work as one integrated team that produces quality, timely and accurate intelligence. And let us be honest, this is a tough task. But this will be Jim's core mission, he is eminently qualified, and he has my complete confidence and support," Obama explained.

The president says the U.S. intelligence community has vastly improved since the terrorist attacks on New York and the Pentagon in 2001. But he says December's incident in which a Nigerian man boarded a jet headed for Detroit with explosives hidden in his underwear shows that more work lies ahead.

Mr. Obama is calling on the Senate to quickly approve General Clapper's nomination.

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（来源：VOA 编辑：陈丹妮）