Would the US win a war with China over Taiwan? US lawmakers briefed on the potential outcome

The Chinese defense industrial base is operating at a "wartime footing," and now has a shipbuilding capacity 230 times greater than the U.S.'s, making a potential invasion of Taiwan a not-unlikely outcome.

During the simulation, the cost for all sides was high - there were more than 10,000 casualties - and the U.S. lost 10-20 warships, two aircraft carriers, 200-400 warplanes and more than 3,000 troops were killed over the first three weeks of fighting. 

China loses 90% of its amphibious fleet, 52 major surface warships and 160 warplanes. 

"In our tabletop exercise today, we walked through one simulation of what might happen in a worst-case scenario conflict with China and learned ways we can work together in a bipartisan manner to ensure that America is prepared to be the arsenal of democracy once more if called upon. No matter where or when, the United States and our allies must have the military means to defeat our adversaries," Rep. John Moolenaar, R-Mich., chairman of the committee, told Fox News Digital. 

The report emphasized four key points: 1) Taiwan must "hold the line" of the ground invasion, 2) there is no "Ukraine" model where the U.S. can slowly escalate - it must decide immediately whether it will come to Taiwan's defense, 3) military operations would need to be conducted through Japan and 4) the U.S. needs to immediately increase its supply of anti-ship missiles. 

The bottom line of the report is that China chooses "D-Day," but Taiwan and its defenders must be ready at any moment. The war game assumed a 2026 launch date for China's invasion. 

The scenario operates under the assumption that the U.S. under President-elect Trump would come to Taiwan's defense, though no such promise has been made. It's unclear what Trump would do under such a scenario - he has mused about Taiwan needing to pay the U.S. for giving it defensive aid.

"It certainly would be very helpful if South Korea stood shoulder-to-shoulder with us," said Matthew Cancian, researcher at the Naval War College and lead author of the project. The U.S. would likely move two of the four squadrons it has stationed in South Korea to help with the fight against China over Taiwan. 

The exercise also claimed that unlike U.S. aid to Ukraine, which passes over NATO territory to arrive there, the U.S. would not be able to arm Taiwan without sending in U.S. forces - China's anti-tank or anti-air missiles would threaten any shipments making their way to the island. 

"U.S. forces would have to be directly involved," said Cancian. "There is no way to achieve denying a takeover of Taiwan while also keeping U.S. forces safe." 

And if the U.S. were to come to Taiwan's defense, there would be no time to waste since China is much closer geographically than U.S. forces. "If the U.S. were not to join the fight for two weeks [after an invasion], it would be too late. China would already have too strong a footing," said Cancian. 

Chinese land attack missiles and anti-ship missiles would pose the greatest threat in the theater. Harpoons and coastal defense cruise missiles would be "absolutely critical" to Taiwan's defense, according to the wargame exercise. 

China is outproducing the U.S. on airplanes, ships and missiles, the exercise found, and in order to deter them from provoking war over Taiwan, the U.S. needs to immediately ramp up its production of key munitions, per the war games. 

The U.S.'s current stockpile of anti-ship missiles, around 440, would run out in less than seven days in a war with China. 

China would not be keen to give up easily, as a loss in Taiwan could be "very destabilizing" to the government's legitimacy back at home. 

The war games also underscored the need for the Taiwanese defense budget to stop focusing on expensive, large ships that China will easily destroy and focus on smaller, more survivable ships and submarines. 

The U.S., too, must focus on arming Taiwan with smaller ships and cheaper munitions, with most iterations of the war games finding the U.S. losing two aircraft carriers and 10 to 20 large surface combatants. 

The U.S. and Taiwan must not attack the Chinese mainland, both to avoid risking escalation with a nuclear power and because Chinese air defense on the mainland is "too strong." 

Ultimately, such an invasion could happen sooner, or not at all. 

The U.S. Indo-Pacific Command (INDOPACOM) head, Adm. Samuel Paparo, said recently he believes the U.S. would make it "exceedingly difficult" for China to mount a cross-strait invasion. 

According to Chinese policy, the CCP will invade only if Taiwan declares its independence from China, if a third power intervenes in the dispute or Beijing determines that "unification was irrevocably beyond its reach by any other means."

"This included on one particular day 152 vessels at sea," Paparo added.

China's navy is the largest in the world, with more than 370 ships and submarines. The U.S.' battle force includes 295 vessels, including 11 active aircraft carriers.