Intel chief: Pressured Iran might strike in U.S.

Director of National Intelligence James Clapper, listens to a question while testifying on Capitol Hill in Washington, Tuesday, Jan. 31, 2012, before the Senate Intelligence Committee hearing to assess current and future national security threats.
AP Photo/Jacquelyn Martin

Top United States intelligence officials had a dire warning for Congress on Tuesday; that Iran would likely launch terrorist attacks on U.S. soil as pressure mounts against the regime in Tehran.

The alarming assessment is making a tense situation even more serious.

The briefing by the nation's top intelligence officers added another ominous development to the possible showdown with Iran.

In his written statement, Director of National Intelligence James Clapper said last year's abortive plot to assassinate Saudi Arabia's ambassador in Washington "shows that some Iranian officials -- probably including Supreme Leader Ali Khamenei -- have changed their calculus and are now more willing to conduct an attack in the United States."

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And the chairwoman of the Senate Intelligence Committee, Diane Feinstein (D, Calif.) said the showdown could come to a head this year. "I think," she said, "2012 will be a critical year for convincing or preventing Iran from developing a nuclear weapon."

Amid the warnings, a U.N. nuclear team announced plans Wednesday to revisit Tehran "in the very near future," indicating some progress on its efforts to get information from Iran about allegations that it is secretly working on a nuclear weapons program.

Some U.S. officials believe Israel could launch a strike to destroy Iran's nuclear facilities as soon as this year. "This is a very sensitive issue right now," Clapper said. "We're doing a lot with the Israelis, working together with them."

The head of Israel's Mossad intelligence agency visited the U.S. last week and met with CIA Director David Petraeus, who also has been meeting regularly with Israel's defense minister. The U.S. is counting on economic sanctions to pressure Iran into giving up its nuclear ambitions before Israel feels compelled to strike. So far, it's not working.

Said Clapper: "The sanctions as imposed so far have not caused them to change their behavior or their policy."

But new sanctions, including a ban on Iranian oil sales to Europe, are just now taking effect.

"The overall situation," Petraeus said, "is one in which the sanctions have been biting much, much more -- literally in recent weeks -- than they have until this time."

Petraeus said it will be months before the sanctions take full effect. Israeli officials have said they can only afford to wait about 6 to 9 more months before they have to strike.

To See David Martin's report, click on the video video in the player above.

Also, "CBS This Morning" senior correspondent John Miller, a former FBI and counter-intelligence official, offer his analysis to co-host Charlie Rose, saying Iran may be scouting possible U.S. targets already so, if Tehran opts to go ahead, it could just pull the information "off the shelf." To get Miller's insight, click on the video below:

  • David Martin

    David Martin is CBS News' National Security Correspondent.