The United States faces a "grave crisis of national security and national defense," according to a Wednesday report by a commission investigating President Donald Trump's military strategy.

The National Defense Strategy Commission, made up of a 12-person panel of former Democratic and Republic officials selected by Congress, evaluated the Trump administration's National Defense Strategy (NDS) of January 2018. The strategy has called for a reshaping of the US military with more of a focus on competition between great powers.

The report suggested that if the US went to war with countries such as China and Russia, it may not win.

"The US military could suffer unacceptably high casualties and loss of major capital assets in its next conflict. It might struggle to win, or perhaps lose, a war against China or Russia," the commission said. "The United States is particularly at risk of being overwhelmed should its military be forced to fight on two or more fronts simultaneously."

The report said the US' military superiority had "eroded to a dangerous degrees" and that its ability to defend itself, its allies and its foreign interests was "increasingly in doubt."

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No clear approach

The commission, which reviewed classified documents and interviewed Pentagon officials, approved of the White House's strategic aims, hailing the NDS it as "a constructive first step," but questioned how national defense goals would be met.

The report said the Trump administration "too often rests on questionable assumptions and weak analysis" and does not provide "clear approaches to succeeding in peacetime competition or wartime conflict" against the US' military rivals.

"We believe the NDS points the Department of Defense (DOD) and the country in the right direction, but it does not adequately explain how we should get there."

"Absent a more integrated, whole-of-government strategy than has been evident to date, the United States is unlikely to reverse its rivals' momentum across an evolving, complex spectrum of competition."

Bulking up NATO

The report noted Russia's recent aggression in eastern Europe, its cyber operation and its changes to its nuclear arsenal as threats the US and its NATO allies has to address.

Though it didn't go so far as to openly criticize NATO as Trump has done throughout his presidency, the commission did highlight the need for the alliance to strengthen its military capacity.

"To deter a revanchist Russia, the United States and its NATO allies must rebuild military force capacity and capability in Europe."

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The report also reflected on the dangers posed by "transnational threat organizations," specifically Islamist terror groups in the Middle East, saying US involvement in the region "cannot be wished away."

"As long as terrorism is exportable, as long as the Middle East remains a major producer of oil, and as long as the United States has key US allies and partners in the region, US interests in the Middle East will be profound."