A week after it was alleged China infringed on U.S. airspace with a spy balloon, the U.S. Air Force launched a missile test in California to demonstrate the country’s nuclear readiness.

The Air Force launched an unarmed Minuteman III intercontinental ballistic missile (ICBM) test late Thursday from Vandenberg Space Force Base in California, according to Fox News.

“The ICBM’s test reentry vehicle traveled approximately 4,200 miles to the Kwajalein Atoll in the Marshall Islands,” the Air Force reported in an announcement.

The launch was a routine activity “intended to demonstrate that the United States’ nuclear deterrent is safe, secure, reliable, and effective,” the base said in an announcement.

“A test launch displays the heart of our deterrence mission on the world’s stage, assuring our nation and its allies that our weapons are capable and our Airmen are ready and willing to defend peace across the globe at a moment’s notice,” Gen. Thomas A. Bussiere, Air Force Global Strike Command commander said, as per the announcement.

“This launch showcases the redundancy and reliability of our strategic deterrence systems while sending a visible message of assurance to allies,” explained Col. Christopher Cruise, 377th Test and Evaluation Group commander.

“This multilateral team reflects the precision and professionalism of our command and our joint partners,” Cruise added.

This missile test was conducted after a show of force from North Korea’s military, which put on its largest-ever display of ICBMs in a parade. A total of 12 individual Hwasong-17 ICBM launchers were escorted down the capital of Pyongyang’s streets, flanked by marching soldiers, according to the BBC.

Analysts say these North Korean launchers could fire missiles, in theory, capable of reaching the U.S. mainland.

While the timing of the U.S. tests might suggest that the Far East’s recent display of military capabilities may have prompted them, military officials have said that the Air Force and its agencies had been planning the tests for months, Fox News reported.

As for the recent discovery of a Chinese spy balloon in U.S. airspace, according to Department of Defense press secretary Brig. Gen. Patrick Ryder, these surveillance practices have long been known about and reach much farther than the U.S.

As The Dallas Express recently reported, Ryder told reporters on Wednesday that other potential spy balloons had been traced passing over the U.S., Canada, Costa Rica, and Japan, among others, and that this alleged Chinese aerial surveillance program had “been operable for several years.”

The U.S. has since received more unwanted visitors, announcing it shot down a high-altitude object in Alaska on Friday. The object was smaller and “likely less sophisticated” than the alleged Chinese balloon shot down last week, CNN reported.

“I’ve driven this point home for years, and we have now been reminded twice in the past week: Alaska is the first line of defense for America,” Alaska Sen. Lisa Murkowski said in a statement.