Gen. Joseph F. Dunford, the nominee to be chairman of the Joint Chiefs of Staff, called Russia's behavior "nothing short of alarming" at a Senate Armed Services Committee hearing on his nomination. (Reuters)

Gen. Joseph F. Dunford, the nominee to serve as the next chairman of the Joint Chiefs of Staff, told the Senate Armed Services Committee on Thursday that Russia poses the greatest security threat to the United States, and said it is reasonable to send Ukraine heavy weapons to defend against Russian aggression.

The general advocated updating the way the Pentagon plans for hybrid warfare, in which conventional military actions are combined with secretive operations such as arming separatists from another country. Russia’s nuclear weapons, combined with its recent actions, make it a threat to take seriously, Dunford said.

“If you want to talk about a nation that could pose an existential threat to the United States, I’d have to point to Russia,” Dunford said. “If you look at their behavior, it’s nothing short of alarming.”

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Dunford listed China, North Korea and the Islamic State militant group as the next most significant security threats to the United States, in that order.

U.S. officials have said there is a steady flow of Russian troops and military equipment into Ukraine since Russia annexed Crimea in early 2014 and backed separatists in eastern Ukraine. In recent days, some Russian lawmakers also have called for Moscow to investigate whether the independence of former Soviet states Latvia, Estonia and Lithuania has any legal standing, drawing a wary eye from NATO nations.

Dunford, the current Marine Corps commandant, said that if he is confirmed as the Pentagon’s new top general, he will try to maintain a relationship in which the U.S. and Russian militaries are capable of preventing a “miscalculation” that could lead to greater conflict between the two countries. He is expected to be confirmed easily.

Under questioning from Sen. John McCain (R.-Ariz.), the committee chairman, Dunford said he believes it is reasonable for the Pentagon to supply heavy weapons like Javelin or TOW missiles that are capable of taking out Russian tanks and counter-battery weapons that can stop rocket or artillery strikes. That mirrors the current Joint Chiefs chairman, Army Gen. Martin E. Dempsey, who called in March for the United States to consider providing lethal aid to Ukraine.


Marine Gen. Joseph F. Dunford testifies before the Senate Armed Services Committee on his nomination to be the chairman of the joints chiefs of staff At right is Dunford’s family: wife Ellyn Dunford, son Patrick, and daughter Kathleen. AFP PHOTO/MANDEL NGANMANDEL NGAN/AFP/Getty Images

“Chairman, from a military perspective I think it’s reasonable that we provide that support to the Ukrainians,” Dunford said. “And frankly, without that kind of support, then they’re not going to be able to protect themselves against Russian aggression.”

The hearing covered a variety of other issues, including future defense budgets, the war in Afghanistan and the military campaign against the Islamic State.

Asked by Sen. Jeff Sessions (R.-Ala.) if the United States should embed military advisers in the Iraqi army allow them to serve in combat missions, Dunford said that he didn’t want to appear evasive, but wanted to get on the ground and speak to commanders before providing a recommendation.

But Dunford did back the current U.S. strategy of working alongside a unified Iraqi government, rather than dealing with the competing ethnic groups there.

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“At this point, I believe that’s the best prospect for long-term success, is a unified multisectarian government in Iraq,” Dunford said. “Frankly, if confirmed, if at any point I no longer believe that’s possible, then my advice to the president will be adjusted accordingly.”

In Afghanistan, Dunford said he will advocate for the United States to withdraw its forces based on the conditions on the ground, rather than a timetable set by the White House.

“My experience has been that sometimes the assumptions that you make don’t obtain, particularly with regard to time,” Dunford said, under questioning from McCain. “And that’s certainly the case in Afghanistan.”