China's military buildup and push to develop nuclear-capable missiles is on full display for the world to take note, and Gen. Mark Milley, chairman of the joint chiefs of staff, says it is "clearly challenging" the United States.

In remarks at the Aspen Security Forum on Wednesday, Milley said the pace at which China is developing military capabilities is "stunning," and on track to surpass the United States "if we don't do something to change it."

"We're witnessing one of the largest shifts in global geo-strategic power the world has witnessed," he declared. "They are clearly challenging us regionally and their aspiration is to challenge the United States globally."

Milley pointed Bejing's test in August of a hypersonic weapon that partially orbited Earth, reentered the atmosphere and rocketed towards its target, missing it by less than 30 miles.

Milley called the test "very concerning" and "very close" to being a "Sputnik moment," referring to the Soviet Union's 1957 launch of the world's first space satellite that gave Moscow a lead in the space race and shocked the United States.

China has maintained the test was "a spacecraft, not a missile," The Hill reported.

But at the forum, Milley called the launch indicative of "a much, much broader picture of a military capability with respect to the Chinese."

"Today [China] has capabilities in space and cyber, land, sea, air, undersea, and they are clearly challenging us regionally," Milley said.

"So we have a case here of a country that is becoming extraordinarily powerful, that wants to revise the international order to their advantage. That's going to be a real challenge over the coming years. In the next 10, 20 years. That's going to be really significant for the United States."

The view was reflected in the Pentagon's latest report on China's military power, released Wednesday, that details its aggressive buildup of its nuclear stockpile, development of new missile capabilities and bolster its armed forces, even in the midst of the COVID-19 pandemic.

"Despite challenges posed by the COVID-19 pandemic, Beijing continued its efforts to advance its overall development including steadying its economic growth, strengthening its armed forces, and taking a more assertive role in global affairs," according to the 192-page report.

China since 2018 has been named as the top defense threat to the country alongside Russia, but its latest advancements had congressional Republicans this week sounding the alarm on its growing threat, The Hill reported.

"We are in the most, I believe, the most endangered position our country has ever been in terms of what China is demonstrating, clearly, what they have the capability of doing," the Senate Armed Services Committee Ranking Member Sen. James Inhofe, R-Okla., said Tuesday, The Hill reported.

And after the Pentagon's report, Rep. Mike Rogers, R-Ala., ranking member of the House Armed Services committee, said in a statement the United States needs to respond to China with "unprecedented defense modernization," The Hill reported.

"This report should crystallize for the Biden administration what has been self-evident for some time – that China poses a real and imminent threat," he said. "Kicking the can down the road for our own military modernization is no longer an option."

Though experts and officials worry China's growing military might is indicative of plans to eventually seize control of Taiwan, the self-governed island that Beijing views as a rogue part of its territory, Milley said at the security forum that China likely would not make a move in the near future, adding: "But anything can happen."

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