Ships and submarines from the Republic of Singapore Navy and U.S. Navy in formation in the South China Sea during the underway phase of Cooperation Afloat Readiness and Training Singapore 2015. CARAT is an annual, bilateral exercise series with the U.S. Navy, U.S. Marine Corps and the armed forces of nine partner nations. (Joe Bishop/U.S. Navy)

WASHINGTON — China’s armed forces are gaining strength and the country is likely speeding up expansion of its nuclear stockpile as part of an effort to expand its influence and control in the Indo-Pacific region, U.S. defense officials concluded in the Pentagon’s annual assessment of Beijing’s military power.

The Defense Department outlined those concerns and others for Congress in its China Military Report. It details top concerns about China’s military, including increased capabilities, based on the most recent data and intelligence from 2021 and part of 2022.

China is basing much of its activity on meeting three major milestone dates — the “mechanization, informatization and intelligentization” of its military by 2027, complete modernization of its national defense and armed forces by 2035, and full “national rejuvenation” by the 100th anniversary of its communist government in 2049, the nearly 200-page report concludes.

The “great rejuvenation of the Chinese nation” is the name of a grand vision by President Xi Jinping to increase Beijing’s global reach and influence and restore the national greatness of early Chinese dynasties. It evokes memories of China as “the Middle Kingdom” that demands “tribute from the rest of the world,” according to the Council on Foreign Relations, a think tank based in New York. Xi has been promoting the great rejuvenation for about a decade.

Modernizing the People’s Liberation Army, which is China’s main military force, means expanding nuclear capabilities. Beijing has about 400 operational nuclear weapons, and if it meets the modernization milestone in 2035 that number will rise to 1,500, according to the Pentagon.

“In 2021, Beijing probably accelerated its nuclear expansion,” the report states. “[China] is investing in and expanding the number of its land-, sea-, and air-based nuclear delivery platforms and constructing the infrastructure necessary to support this major expansion of its nuclear forces. The [country] is also supporting this expansion by increasing its capacity to produce and separate plutonium by constructing fast breeder reactors and reprocessing facilities.”

The 2027 milestone aims for technological and modernization advances in China’s armed forces that will give Beijing a “more credible military tool” to wield as it pursues Taiwan unification, according to U.S. defense officials in the report.

The Defense Department has given Congress its annual report on China’s military power since the start of the 2000s to inform lawmakers of key changes to the country’s military capabilities from year to year. The main findings in this year’s report, officials said, are Beijing has become “increasingly clear” with its intentions and is determined to “amass and expand its national power” to transform the international system to one that’s more favorable to China’s interests.

Another key finding, officials said, is one of increasing Chinese military “coercion” outside its borders, notably in the South China Sea and other strategic locations in the Indo-Pacific region.

“We have seen over the course of 2021 and also including in some of the areas that we cover in 2022 in the report, a trend of more coercive military behavior,” a senior U.S. defense official told reporters on Monday. “So, we've seen more coercive and aggressive actions in the Indo-Pacific region, including some of which we would highlight as being dangerous.”

Those actions include an increase of “unsafe and unprofessional behavior” from Chinese vessels and aircraft in the Indo-Pacific region that could threaten and become dangerous for other vessels and aircraft operating nearby, the official said.

Additionally, the Pentagon said China is strengthening its nuclear and space capabilities and is intensifying military pressure against Taiwan, which it has long considered a breakaway Chinese territory. The report said Chinese pressure against Taiwan even increased after House Speaker Nancy Pelosi, D-Calif., visited the island in August, against warnings from Beijing.

The country’s escalating rhetoric about Taiwan and its rising influence in the Indo-Pacific were two major concerns outlined last month in the Pentagon’s National Defense Strategy. In that assessment, the Defense Department identified China as the top global competitor for the U.S. due to its growing military prowess and widespread economic and military influences.

Defense Secretary Lloyd Austin in Cambodia last week for a security summit voiced concerns to Gen. Wei Fenghe, the Chinese defense minister, about “increasingly dangerous behavior” demonstrated by Chinese aircraft in the Indo-Pacific — and vowed U.S. forces will “continue to fly, sail and operate wherever international law allows.”

Tuesday’s report underscored those same concerns and reiterated U.S. views that there are international waters in the South China Sea, including the Taiwan Strait.

“Throughout 2021, the PLA increased provocative and destabilizing actions in and around the Taiwan Strait. The PRC could conduct a range of options for military campaigns against Taiwan,” the report states, using an acronym for China’s formal name, the People’s Republic of China. “These options may range from an air and/or maritime blockade to a full-scale amphibious invasion to seize and occupy some of its offshore islands or all of Taiwan.”

Furthermore, China has made recent efforts to “erode U.S. and partner influence,” such as highlighting the U.S. withdrawal from Afghanistan in August 2021 and criticizing U.S.-backed security partnerships such as the Quad, a defense pact comprised of the U.S., Australia, India and Japan, according to the Pentagon report.

The PLA’s army has almost 1 million active-duty troops ready to fight in combat units and its navy is the largest in the world with a battle force of 340 ships and submarines, the Pentagon said.

The PLA has close to 2,300 combat aircraft in its air force and naval aviation fleet, the report notes, and the air force is “rapidly catching up to Western air forces” through increased domestic production and a larger number of military drones. Beijing’s ongoing military advances have further strengthened its overall ability to fight and win wars against a strong enemy, such as the United States.

President Joe Biden and U.S. defense officials have recently expressed new concerns about China’s plans for Taiwan — especially after Russia’s invasion of Ukraine, which Moscow considers a breakaway territory. Moreover, Biden has pledged to defend Taiwan militarily if it’s attacked or invaded by China.

“We take very seriously our responsibility to help provide Taiwan the self-defense capabilities that it needs,” John Kirby, National Security Council coordinator for strategic communications, told reporters on Monday. “That’s in accordance with law and policy and that’s not going to change.”

Kirby said there’s a balancing effort going on within the Biden administration to ensure Taiwan has what it needs from the United States, considering the Pentagon has been giving large amounts of aid and equipment to Ukraine this year.

“Overall, this report really underscores why we talk about China as the pacing challenge for the [Pentagon],” a senior defense official told reporters. “[China] is really the most consequential and systemic challenge to our national security and to a free and open international system.”