The risk of war with China is real and the United States risks losing the conflict unless greater preparations are made, President Trump’s pick for a key Pentagon policy post told a Senate confirmation hearing on Tuesday.

Elbridge Colby, the nominee for the key position of undersecretary of defense for policy whose selection sparked some divisions among conservatives, called for limiting the use of military force and restoring American defense industrial might to fix the military.

Mr. Colby said the United States is facing “deep peril” from China, along with other foes like Russia, Iran and North Korea.

“Peace and the protection of American interests in the world cannot be assumed,” Mr. Colby told the Senate Armed Services Committee. “There is a real risk of major war and we cannot afford to lose one.”

The comments contrasted with the Biden administration view that war with China was neither imminent nor inevitable.

Adm. Sam Paparo, commander of the Indo-Pacific Command, highlighted the danger recently in a speech stating that large-scale Chinese military exercises near Taiwan were not drills but “rehearsals” for a future attack.

Mr. Colby testified that he hopes the United States can get through the coming years peacefully through new policies he called “America first” and “peace through strength.”

Committee Chairman Roger Wicker said Mr. Colby appeared to “soften” his support in recent months for the defense of Taiwan against an attempted Chinese annexation. He also questioned Mr. Colby about past comments opposing the use of military force to prevent Iran from obtaining nuclear weapons.

Mr. Colby said in the past that Americans could survive without a free and open Taiwan, and that preventing a Chinese takeover is not essential to U.S. security.

Mr. Colby said in response Tuesday that losing Taiwan would be “a disaster” and said his past comments were based on the military balance of power across the Taiwan Strait “dramatically deteriorating” because of Chinese military advances.

“What I have been trying to shoot a signal flare over is that it is vital for us to focus and enable our own forces for an effective and reasonable defense of Taiwan, and for the Taiwanese and the Japanese to do more,” he said.

The No. 1 priority if confirmed for the post would be to prepare for a conflict with China over Taiwan as rapidly as possible and over the longer term, he said.

Democrats on the panel used the confirmation hearing to press Mr. Colby to say whether or not Russia invaded Ukraine, in response to comments by Mr. Trump that Ukraine was responsible for starting the war in 2022. Mr. Colby declined, stating he did not want to upset delicate diplomacy currently underway on ending the conflict.

Russia, however, poses a significant military threat to Europe and the United States, he said.

Asked by Rhode Island Sen. Jack Reed, the panel’s ranking Democrat, about comments that the U.S. should reduce its support for Ukraine to better counter China’s designs on Taiwan, Mr. Colby said his goal is to “re-industrialize” the country’s defense infrastructure to better be prepared to fight wars in multiple theaters.

Mr. Colby also said he supports the NATO alliance but he agrees with Mr. Trump that European nations must sharply increase their defense spending levels and improve combat capabilities to reduce levels of the U.S. burden in the alliance.

“I believe that the NATO alliance has been an exceptionally successful alliance. But I think if we’re going to sustain it, it needs to move in the direction President Trump is leading,” he said.

The nominee also distanced himself from two current Trump appointees at the Pentagon who have voiced neo-isolationist views, Michael DiMino and John Andrew Byers.

Mr. Wicker said Mr. DiMino, deputy assistant defense secretary for the Middle East, has said there are “no vital or existential U.S. interests in the Middle East.”

Mr. Byers, a Southeast Asia policymaker, opposes viewing China through the lens of deterrence and has said the United States should give up “belligerent” policies toward China, Mr. Wicker said.

Mr. Colby said he disagrees with both officials’ views and that they do not reflect Mr. Trump’s policies. “What I would commit to you is that anybody in my organization should be in line with the president’s agenda,” Mr. Colby said when asked if he would retain Mr. DiMino and Mr. Byers if confirmed by the Senate.

On another issue, Mr. Colby said he supported building the new strategic systems — the new intercontinental ballistic missile called the Sentinel, Columbia-class missile submarines and the B-21 strategic bomber.

Under questioning from Sen. Tom Cotton, Arkansas Republican, Mr. Colby promised that he would provide credible military options to the president to counter a nuclear-armed Iran.

Mr. Cotton said a lack of military options against Iran would make it more difficult for the Trump administration to reach a nuclear deal with Tehran. Asked to explain the softening of his views on the defense of Taiwan, Mr. Colby said he has always viewed Taiwan as important but “not an existential interest.”

Mr. Colby said the United States has provided implicit support for Taiwan’s defense but that the increased threat from China and lack of U.S. preparedness are behind his views on diminished support for a defense of Taiwan. Taiwan’s defense spending of less than 3% of GDP should increase to “more like 10%” he said.

In a sign of administration support, Vice President J.D. Vance introduced Mr. Colby and said the nominee believes that military power is “downstream from economic power.”

Mr. Vance said the United States must rebuild the defense industrial base so that American troops can have the weapons and ammunition they need. “That’s not a simple matter of throwing money at the problem,” Mr. Vance said.

On the efforts to jettison “woke” Pentagon policies under Mr. Trump, Mr. Colby said he supported policies restoring a focus on military lethality and merit. And Mr. Colby said he fully supports Mr. Trump’s vision for a nationwide missile defense dubbed “Golden Dome.”

Technology breakthroughs in drones and artificial intelligence can drive down costs and increase the ability to build the system, he said.

• Bill Gertz can be reached at bgertz@washingtontimes.com.