The cold war is officially back.

The Senate Armed Services Committee is currently hearing the testimony of retired Marine General James Mattis, picked by Donald Trump to take over the Department of Defense.

Mattis retired from the US Marine Corps in 2013 after serving as the 11th commander of US Central Command, replacing General David Petraeus as the overseer of US operations in the Middle East and Afghanistan. His appointment requires a congressional waiver because federal law states that service members must wait seven years after retiring from active duty before they can hold senior civilian defense positions.

As the WSJ notes, "so far, there is no sign that he will face any resistance on for his Senate confirmation. He's winning a fair amount of praise from Democrats. It this continues to hold, he could have one of the smoothest confirmation votes of any Trump administration nominee."

“Our Armed Forces must remain the best led, best equipped, and most ready force in the world,” Mattis told the Senate. “We must also embrace our international alliances and security partnerships. History is clear: nations with strong allies thrive and those without them wither.”

“My watchwords will be solvency and security in providing for the protection of our people and the survival of our freedoms,” Mattis said. “America has two fundamental powers. One is intimidation,” Mattis told Senator Gary Peters (D-Michigan). “The other power, which we’ve used less in the last 20 years, is the power of inspiration.” The US should not be turning to military power as the answer to all of its concerns around the world, the retired Marine general added.

Here are some of the key highlights so far:

Russia Is "Principal Threat" To US Security

While much of the hearing has so far been without controveries, in the most striking moment so far, Mattis told the Senate Armed Services Committee that Russia stands as the "principal threat" to the United States's security. He said this is because of its actions and efforts to "intimidate" other countries.

Senator John McCain questioned Mattis to get his opinion on how much of a threat Russia represents. Mattis response was that "the world order is “under biggest attacks since WW2, from Russia, terrorist groups, and China’s actions in the South China Sea,”, agreeing with the neocon senator that Russia is trying to break up NATO.

“I’m all for engagement” with Russia, “but we also have to recognize the reality of what Russia is up to,” Mattis told Senator Jack Reed (D-Rhode Island).

Senator Martin Heinrich (D-New Mexico) questioned if Mattis would stand up to generals, citing the Cuban missile crisis and bringing up the general’s moniker of ‘Mad Dog.’ “That nickname was given to me by the press,” Mattis said, adding his approach would be “Peace through strength” established by the first US president, George Washington – and often invoked by Trump.

Asked by Heinrich to list the principal threats to the US, Mattis said he “would start with Russia,” and continue with aggressive states and terrorist groups.

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Defense Spending And the F-35

Mattis was probed on issues of defense budget cuts due to the legislation introduced by President Barack Obama in 2011. “I don’t have a solution for… the self-inflicted wound of the Budget Control Act,” Mattis told Sen. Claire McCaskill (D-Missouri), but promised he would spend the Pentagon’s budget on what it should be spent on.

“If I can’t make an argument to you for why we need a military program, I am willing to lose it,” Mattis told Senator Mike Rounds (R-South Dakota), explaining that the sequester takes away that decision from the Congress and mandates across-the-board cuts.

Mattis also defended the construction of F-35 fighter jet that Trump criticized as expensive and ineffective.“Many of our allies have bet their air superiority on the F-35 program,” Mattis acknowledged to Senator Richard Blumenthal (D-Connecticut).

Trump’s tweets about military acquisitions “show he’s serious” about getting the best value for the defense dollars spent, Mattis said, disagreeing with Hirono that such actions were inappropriate. He also backed the president-elect’s position about US allies needing to contribute their fair share. Senator Joni Ernst (R-Iowa) brought up her prior military service to criticize “outdated small arms and ammunition,” singling out the M9 pistol and the M-16 assault rifle.

As the WSJ adds, Mattis throws his support behind President-elect Donald Trump's approach to chastising defense contractors about their costs. Gen. Mattis says this shows Mr. Trump is "serious about getting the best bang for the dollar when it comes to defense dollars."

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US Friends and Allies

First and foremost, Mattis listed Israel as one of US' top allies: “Israel is a fellow democracy and I think Israel’s security is very important to the US,” Mattis told Sen. Roger Wicker (R-Mississippi).

“Are there any other democracies in the Middle East?” Wicker asked. “No,” Mattis said.

Senator Jeanne Shaheen (D-New Hampshire) asked about the US troops in Poland in the context of US “reassuring” NATO allies. “NATO is the most successful military alliance probably in modern world history, maybe ever,” Mattis said, but mistakenly argued that “the first time NATO went into combat” was after the 9/11 terrorist attacks.

“The Pacific theatre remains a priority in my mind,” the retired Marine general reassured Senator Mazie Hirono (D-Hawaii). “We have worldwide responsibilities and certainly the Pacific looms large in that.”

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On the US National Debt

In one of the more notable exchanges, Sen. David Perdue asked Mattis to weigh in on the national debt, and Gen. Mattis says the debt is the primary challenge facing the United States. "We cannot solve this debt problems on the backs of our military alone," Gen. Mattis said. He said Congress must "prioritize where this money is being spent." He said there should not be a transfer "of a debt of this size to our children."

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