Gen. Mark A. Milley, the chairman of the Joint Chiefs of Staff, alerted Mr. Biden.
By Wednesday, when the balloon had made its way to the skies above Billings, Mont., Pentagon officials were alarmed because the state is home to the 341st Missile Wing at Malmstrom Air Force Base, one of three U.S. Air Force bases that operate and maintain intercontinental ballistic missiles. One Pentagon official described shock at what officials viewed as a blatant, and poorly concealed, effort at spying. A senior Biden administration official called the move audacious.
Secretary of Defense Lloyd J. Austin III, in the Philippines at the time, called a meeting on Wednesday of senior military and defense officials to review military options, per Mr. Biden’s order. General Milley and Mr. Austin advised against shooting down the balloon while it was over land.
They also did not alert the public, as officials at the Pentagon, the White House, the State Department, along with the intelligence agencies, discussed what to do. Mr. Blinken’s trip to China was scheduled to begin in days, and the administration had decisions to make.
State Department officials began intense discussions on Wednesday about whether Mr. Blinken should make the trip, a senior administration official said.
Later that day, Wendy Sherman, the deputy secretary of state, summoned to the State Department a senior Chinese diplomat, who arrived around 6:30 p.m. Ms. Sherman and Mr. Blinken told the official his government’s spying activities were unacceptable and demanded that China remove the balloon from U.S. airspace, American officials said.
Ms. Sherman and Mr. Blinken told the diplomat that the balloon would have a serious impact on Mr. Blinken’s planned trip. Mr. Blinken also said the United States had the right to take action to protect its national interests, alluding to the possibility of shooting down the machine.
In Beijing, the U.S. ambassador, R. Nicholas Burns, also told the Chinese Foreign Ministry that its government had to remove the balloon, officials said. Discussions continued behind closed doors.