“This required some tough choices ... and we made them,” he said, “based upon a fundamental precept: namely, that America can afford survival.”

The Obama-era Quadrennial Defense Review called for “preserving strategic stability” with Moscow and Beijing and took a rosier view of the prospects for further nuclear arms reductions in partnership with Russia. Now, the new document asserts in blunt language, both Russia and China must be the U.S. armed forces’ “principal priorities.”

“We will continue to prosecute the campaign against terrorists that we’re engaged in today,” Mattis said, “but great power competition — not terrorism — is now the primary focus of U.S. national security.”

Facing the real possibility of a government shutdown at midnight Friday because of a funding impasse in Congress, Mattis lamented the ongoing budget battles, saying they were doing more damage than any enemy.

“In this time of change, our military is still strong, yet our competitive edge has eroded in every domain of warfare — air, land, sea, space, and cyberspace,” he asserted, “and it is continuing to erode.”

The new defense strategy indicates that President Donald Trump’s military advisers are looking beyond the conflicts of the moment, including North Korea’s nuclear ambitions, the wind-down of the war against ISIS and concerns about Iranian influence in the Middle East.

The strategy also departs from some of Trump’s own past rhetoric, including his admiration for Russian President Vladimir Putin and skepticism about NATO, although it matches his years of warnings about American power being in decline.

“The erosion of our military advantage is the problem that the strategy is trying to deal with,” Elbridge Colby, deputy assistant Defense secretary for strategy and force development, told reporters in previewing the new strategy on Thursday.

Russia and China “have decided to go to school on the American way of war and the technologies that are associated with it,” he added, “and have made a lot of headway.”

While the new focus is “not a strategy of confrontation,” he stressed it’s designed to address “very tough major power potential challenges.”

The full strategy document is secret, but an 11-page, unclassified summary broadly outlines where the U.S. needs to make new investments in its fighting forces and technology.

Topping the list is modernizing the nuclear arsenal as a way of deterring both rising powers. The new strategy also emphasizes making space systems and other critical communications more resilient to physical and cyber attacks; deploying more missile defense systems to protect U.S. forces and the American homeland; stockpiling more battlefield weapons and other supplies in strategic locations around the world; and more aggressively introducing “advanced autonomous systems.”

The document also calls for “rapid application of commercial breakthroughs” to harness artificial intelligence and machine-learning technology to ensure American military supremacy.

It bluntly describes what Pentagon leaders see as two major long-term threats to the Western interests.

“Russia seeks veto authority over nations on its periphery,” the strategy says, and through economic and diplomatic means is seeking to “shatter the North Atlantic Treaty Organization,” the Western alliance that served as the bulwark against Soviet expansion into Europe during the Cold War.

“The use of emerging technologies to discredit and subvert democratic processes in Georgia, Crimea and eastern Ukraine is concern enough,” the document adds, “but when coupled with its expanding and modernizing nuclear arsenal the challenge is clear.”

It also stands out amid the president’s hesitance to criticize Russia. But it’s consistent with language in a broader National Security Strategy released last month by the White House, which also described increasingly aggressive competition from what it called “revisionist powers,” Russia and China.

Colby, though, said an emphasis on strengthening and building new alliances will also mean “more balanced burden-sharing arrangements with our allies and partners” — a nod to Trump’s repeated accusations that NATO and other allies are not pulling their weight.

China, meanwhile, “is leveraging military modernization, influence operations, and predatory economics to coerce neighboring countries to re-order the Indo-Pacific region to their advantage,” the strategy declares.

And the Chinese military modernization program, it adds, is designed to achieve “regional hegemony in the near-term and displacement of the United States to achieve global preeminence in the future.”

But while the Chinese and Russian militaries have forged ahead, the U.S. is “emerging from a period of strategic atrophy,” the strategy contends.

It asserts the U.S. military has lost major advantages it long maintained in the air, on the land, in space and in the nuclear arena.

The blueprint sends a strong signal the Trump administration is committed to maintaining the military balance of power, as Colby put, in “the key regions that we’ve been in since the late 1940s” — including in Asia, Europe and the Middle East.

Still, Colby cautioned it should not be read as signaling abandonment of the threats the military has recently focused on, like Iran, North Korea and Islamist terrorist groups.

“This is definitely not a pivot strategy in the sense of pivoting away from the Middle East or something like that,” Colby explained. “We know we’re going to be dealing with terrorism somewhere or another for the long haul, so let’s find ways of dealing with it that are more cost-effective, more tailored, so we can walk and chew gum at the same time.”

The strategy diagnoses what it calls a “resilient, but weakening, post-WWII international order.”

“In the decades after fascism’s defeat in World War II, the United States and its allies constructed a free and open international order to better safeguard their liberty and people from aggression and coercion,"" the document says. “China and Russia are now undermining the international order from within the system by exploiting its benefits while simultaneously undercutting is principles and ‘rules of the road.’”

On Capitol Hill, the new strategy drew praise from the Senate and House Armed Services chairmen, who have called for a major military buildup to meet growing and increasingly complex worldwide threats.

Both Sen. John McCain (R-Ariz.) and Rep. Mac Thornberry (R-Texas) urged Congress to approve higher levels of defense spending.

“Congress must immediately reach a bipartisan budget agreement to provide the funding necessary to implement this strategy,” McCain said in a statement. “Reversing the readiness and modernization crises will require significant investment, and we must start now.”

“If Congress does not come together to find a way to fund this strategy, Secretary Mattis must explicitly inform Congress and the American people of the consequences of that failure,” Thornberry warned in a separate statement.

“What is unacceptable under all circumstances,” he added, “is to continue to ask our troops to do more with less and turn a blind eye to the deadly consequences of a steadily-eroding force.”

Connor O’Brien contributed to this report.