WASHINGTON – The U.S. intelligence community faces a complex challenge moving forward as it combats a variety of overlapping threats, Director of National Intelligence James Clapper told a Senate committee Tuesday. Gone are the Cold War days when much of the nation’s attention focused on the Soviet Union.

“The United States no longer faces — as in the Cold War — one dominant threat,” Clapper said in a prepared testimony. “Rather, it is the multiplicity and interconnectedness of potential threats — and the actors behind them — that constitute our biggest challenge.”

The hearing before the Senate Select Committee on Intelligence assessed an array of potential threats in the Middle East and Asia-Pacific region. These included global and domestic terrorism, nuclear proliferation in Iran and North Korea, and cyber threats from China and Russia.

In opening remarks, Committee Chairwoman Dianne Feinstein called 2011 as a “year of major intelligence successes.”

She said the intelligence community supported countless national security actions including, the killing of Osama Bid Laden and other terrorist leaders, the NATO-led mission in Libya that removed dictator Moammar Gadhafi, and the implementation of sanctions on Iran over its nuclear program.

Feinstein cautioned such successes should not overshadow lingering threats to national security. She said 2012 would be a critical year for preventing the development of nuclear weapons in Iran and North Korea.

“While the overall terrorist threat may be down, the threat from the proliferation of weapons of mass destruction from Iran and North Korea is growing,” she said.

Clapper said the intelligence community’s hope is that sanctions would cause Iran to alter its nuclear policies, which neighboring Israel has characterized as an “existential threat.” According to the assessment, Iran is expanding its uranium enrichment capabilities and its technical advancement shows the country has the capacity to eventually produce nuclear weapons.

The Iranian government insists the nuclear program is for peaceful purposes.

Sen. Ron Wyden, D-Ore., said he believed Iranian leaders would not give up their push for nuclear weapons “unless they believe will cost them their hold on power.”

CIA director David Petraeus said Iran is reportedly trying to be more open to talks, as it feels the increased bite of the new economic sanctions and the reduction in oil purchases from some of its key customers.

Clapper believes Iran’s decision-makers will weigh the costs and benefits of advancing an aggressive nuclear program. Leaders, Clapper said in a statement, would have to consider its “security, prestige, and influence, as well as the international political and security environment.”

Clapper expects North Korea’s change in leadership will not alter the country’s policy on nuclear proliferation. He said its exporting of ballistic missiles and materials to several countries, including Iran and Syria, shows the country’s reach across the globe.

Clapper saw the next two or three years as a “critical” transition period for terrorists groups. With the death or capture of iconic leaders like Bin Laden and other al-Qaida figures, he said the terrorist leadership will become more decentralized and the smaller cells will likely begin budding.

His assessment stated that the rise of al-Qaida’s new leader, Ayman al-Zawahiri, will change the organization’s strategic direction. But Clapper predicted al-Qaida members will find his leadership style “less compelling” and will not galvanize as they did under bin Laden.

“The removal of bin Laden and Anwar al-Awlaki was a huge benefit to security,” said FBI director Mueller. “By the same token, there are still leaders in both Yemen and the Afghanistan-Pakistan border area that have the capability of launching attacks domestically.”

When it came to Afghanistan, Feinstein expressed concern over what will happen in 2014 when troop withdrawals occur and Hamid Karzai’s term as president ends.

“In Afghanistan, the surge of U.S. forces that began in 2009 has produced meaningful gains,” she said. “Frankly, I don’t see a viable strategy for continuing the level of security and stability that we are building after 2014.”

Sen. Olympia Snowe, R-Maine, said U.S. strategy in Afghanistan was predicated on addressing and rooting out safe havens for terrorist cells.

The committee pressed the issue of cyber security as a key national security concern for the future.

Clapper’s assessment showed that China and Russia were critical state actors, but non-state entities such as hacker groups Anonymous and Lulz Security have surfaced to become central players in the world of potential cyber threats.

Sen. Jay Rockefeller, D-W.Va., questioned the progress made in the cyber security sector and how seriously the Obama administration took cyber threats. He and Snowe introduced a bill to the Senate in 2009 that gave the president the power to shut down traffic on a compromised server if he declared a “cyber emergency.”

“If it is the national security threat, I don’t understand why we can’t get, working together on this, and get a bill done,” Rockefeller said.

The intelligence community has made significant progress since the 9/11 attacks, Clapper said. He cited the transformation of the FBI, development of the Department of Homeland Security and increased interagency information-sharing as examples that demonstrate improvement.

“Never before has the intelligence community been called upon to master such complexity on so many issues in such a resource-constrained environment,” Clapper said. “We’re rising to the challenge.”