Biggest Threats to US Include Homegrown Terror, North Korea, Intel Chiefs Say

— -- Top U.S. leaders laid out the major worldwide threats facing the United States at Tuesday's Senate Armed Services Committee hearing -- including homegrown terrorism and North Korea's nuclear program.

"It's a very accurate litany of doom," said Sen. Jim Inhofe (R-OK) during the testimony by James Clapper, the director of National Intelligence, and Marine Corps Lt. General Vincent Stewart, director of the Defense Intelligence Agency.

Here are some of the highlights:

Terrorism in the US:Stewart cautioned against homegrown threats, saying, "ISIL will probably attempt to conduct additional attacks in Europe, and attempt to direct attacks on the U.S. homeland in 2016." In his written statement, Clapper similarly warned that “the perceived success of attacks by homegrown violent extremists in Europe and North America, such as those in Chattanooga and San Bernardino, might motivate others to replicate opportunistic attacks with little or no warning, diminishing our ability to detect terrorist operational planning and readiness.” He said that U.S.-based homegrown violent extremists pose "the most significant Sunni terrorist threat to the US homeland in 2016."

Taking Back Mosul:Stewart said he was not optimistic about taking Mosul from ISIS in the near term, saying it's unlike to happen in the next year. "We may be able to begin the campaign, do some isolation operations around Mosul," he said. "But securing or taking Mosul is an extensive operation and not something I see in the next year or so." Stewart also mentioned there is still work to be done to secure Ramadi.

North Korean Nuclear Power:Clapper said North Korea has expanded their Yongbyon nuclear facility not far from the capital of Pyongyang. “We assess that North Korea has followed through on its announcement by expanding its Yongbyon enrichment facility and restarting the plutonium production reactor," he said. "We further assess that North Korea has been operating the reactor long enough so that it could begin to recover plutonium from the reactor's spent fuel within a matter of weeks to months." On Saturday, North Korea successfully launched a long-range missile, apparently into space.