Gen. Mark Milley, the chairman of the Joint Chiefs of Staff, said on Sunday that the Chinese military has become much stronger over the last five years. Milley made the comments on a trip to Indonesia and amid strained relations between the U.S. and China over trade, human rights abuses of Uyghurs, and a U.S. boycott of the upcoming Winter Games in Beijing.

China’s military growth could cause greater concern in the Pacific. Milley explained that the Chinese military has noticeably increased its amount of military aircraft.

“The message is the Chinese military, in the air and at sea, have become significantly more and noticeably more aggressive in this particular region,” Milley told reporters traveling with him.

There is also concern that a Chinese naval base could be placed in the South Pacific after a defense pact was signed with the Solomon Islands in April. Both the U.S. and Australia have told the Solomon Islands that they won't tolerate a military base on the Pacific Island nation.

China has also made hints that it may attempt to claim Taiwan as a part of its communist mainland as it sees Taiwan as a country that tried to break away. Taiwan is currently a democratic and self-ruled island.

“This is an area in which China is trying to do outreach for their own purposes. And again, this is concerning because China is not doing it just for benign reasons,” Milley said.

“They’re trying to expand their influence throughout the region. And that has potential consequences that are not necessarily favorable to our allies and partners in the region,” Milley added.

In March 2021, Secretary of State Antony Blinken called managing the U.S. relationship with China "the biggest geopolitical test of the 21st century."

"China is the only country with the economic, diplomatic, military, and technological power to seriously challenge the stable and open international system – all the rules, values, and relationships that make the world work the way we want it to, because it ultimately serves the interests and reflects the values of the American people," Blinken said.