By Edward Wong, Julian E. Barnes and Adam Entous

WASHINGTON — Senior American officials increasingly believe the Chinese spy balloon that was shot down off the coast of South Carolina in early February was originally supposed to conduct surveillance over US military bases in Guam and Hawaii, but winds carried it off course to Alaska, Canada and finally the continental United States.

The evolution of Washington’s understanding of the Chinese military’s original goals and new details that reveal misreadings of the US reaction by Chinese officials in private meetings reflect how difficult it is for the United States and China to discern each other’s intentions — a gap that American officials fear could lead to greater mistrust in an already fraught relationship or even to armed conflict.

In another example of the fog created by superpower rivalry and political imperatives, US officials said in interviews on Wednesday (15) that they now increasingly believe three unidentified flying objects shot down over North America were unlikely to be surveillance devices.

US officials said they are still trying to make a definitive conclusion on what the objects were, and do not think they will reach one until more debris is collected. Some senior officials said that based on preliminary work, they believe the three objects were likely designed for scientific or weather research and had ceased to function, becoming akin to airborne trash.

But the fallout from the spy balloon itself continues to escalate tensions between the United States and China even as new revelations around the episode reveal the depths of confusion over it. American officials discussed those revelations on the condition of anonymity because of sensitivities over intelligence and diplomacy.

Some Biden administration officials say that even if the balloon was aimed at the Pacific region, it was designed to spy on the United States and other nations. And Chinese officials did nothing about the balloon as it passed over the continental United States — including above nuclear missile silos in Montana — for days after senior American diplomats first confronted Chinese officials in private over it.

It took almost three days after the public crisis over the balloon erupted for Chinese officials to tell US counterparts that the controllers of the balloon were trying to speed it out of American airspace, an apparent effort to defuse tensions that baffled Biden administration officials and demonstrated how badly Beijing had misread the United States.

By that point, the balloon was reaching the coastline, the American public and politicians had expressed fury over it for days — some criticizing President Joe Biden for not shooting it down immediately — and US officials were intent on getting their hands on it to study its sensors, even if they would end up examining only debris resulting from a missile strike.

An F-22 fighter jet shot the balloon down with a single missile hours later, on the afternoon of Feb. 4.

Other murky actions have challenged US analysts trying to read Chinese intentions. On Jan. 28, when the balloon approached the Aleutian Islands and American airspace over Alaska in its off-course trajectory, the balloon’s self-destruct function did not activate, US officials said. Chinese operators may not have wanted to destroy the balloon; it is also possible that they attempted to trigger the self-destruct mechanism and it failed.

Operators or officials might have mistimed the winds and thought currents would carry the balloon quickly over Alaska and out of American airspace to the Arctic Ocean. Or they might have decided to allow the balloon to continue onward to see what kinds of intelligence it could collect — not foreseeing the diplomatic and political maelstrom that would ensue once the balloon drifted with the winds to the continental United States.

Some American officials say they know the intended trajectory of the spy balloon in part because the U.S. government tracked the balloon from the time of its launch in late January from Hainan Island in southern China, a detail first reported Monday (13) by The New York Times, and observed it as it moved across the Pacific. US agencies also monitored the balloon as it was pushed in different directions by the winds, officials said.

Once the balloon went off course, as US officials suspect, Chinese officials and the machine’s operators, who could be employees of a civilian-run balloon maker under contract with the People’s Liberation Army of China, appeared to make a series of bad decisions.

Chinese operators and officials did not take any immediate action after the two top American diplomats, Antony Blinken, the secretary of state, and Wendy Sherman, the deputy secretary, issued a formal démarche to a senior Chinese diplomat, Zhu Haiquan, at the State Department around 6:30 p.m. on Feb. 1 over the balloon, telling him his government had to do something about it. Zhu appeared taken by surprise, US officials said.

More than 24 hours later, and a half-day after the Pentagon announced the existence of the balloon, Chinese foreign ministry officials in Beijing spoke privately to diplomats in the US Embassy to tell them the balloon was a harmless civilian machine that had gone off course.

Later that Friday, Feb. 3, after China issued a public statement expressing regret, and after Blinken cancelled a planned weekend visit to Beijing, the balloon appeared to accelerate, US officials said.

There is much the US government still does not understand. While the balloon was equipped with small propellers, US intelligence agencies do not believe it had the power to dramatically change speed or direction, some American officials said.

Then early on Saturday (11), Chinese officials told US counterparts that the balloon’s operators were trying to speed it out of American airspace.

By then, the balloon was reaching the Atlantic coast, and Pentagon officials had begun plans to destroy it over the ocean.

While Chinese balloons have previously passed over the continental United States, the American targets of the balloon program appear mainly to be U.S. military bases in the Pacific. Previous reconnaissance missions by the balloons have been relatively short. When two spy balloons passed Hawaii, for example, one drifted over an island quickly and another entered the airspace around the island chain but did not fly over it.

The Biden administration has said the Chinese military’s spy balloon program has sent airships over more than 40 countries on five continents, violating their sovereignty. US officials began learning about the program after 2020, during a broader review of unidentified aerial phenomena. Officials then realized some past instances of aerial objects in US airspace were Chinese surveillance balloons.

Beijing may be developing the program to supplement its satellite intelligence collection and also to have backups for the satellites in the event of war with the United States, American officials say.

“They have 260 intelligence satellites in orbit,” said John Culver, a former US intelligence analyst on China. “They’re a major space power. This can augment that capability.”

Culver added that there was a strong political incentive in the Chinese system for such a program.

“The Chinese government knows the US typically flies hundreds, perhaps more than a thousand, reconnaissance aircraft off their coast every year,” he said. “They’re frustrated they can’t fight back. This program gives them something they can point to internally. This is a program that has political value to them and has wartime value.”

The balloon program is still in a testing phase, so learning what, if any, significant intelligence the balloons can gather from American bases is important for the Chinese military, US officials say. The downed spy balloon had equipment, including antennas, that allowed it to collect electronic communications, and it was transmitting encrypted signals to Chinese satellites. But US officials insist the balloon did not retrieve any information that Chinese satellites and other intelligence assets cannot already collect.

Early findings suggest the balloon’s self-destruct mechanism was intact, US officials say. Navy divers searching for debris off South Carolina have seen a blasting cap meant to destroy the payload, they say. FBI investigators examining recovered debris could potentially determine if some malfunction had prevented the mechanism from working, though several US officials say they now assume that the device was functional.

US officials say Chinese officials likely wanted to avoid activating the mechanism when the balloon was over land, for fear that any injuries or damage it might cause would escalate the crisis quickly. Chinese officials probably also had the ability to deflate the balloon and bring it to the ground, but wanted to try to prevent the Americans from acquiring the surveillance equipment.

Navy divers have collected some parts of the balloon’s sensors. It was equipped with a camera and the antenna array, and the more US officials learn about the devices, the more they are unimpressed with the balloon’s capabilities, they say. In any case, they add, the Pentagon locked down communications and activities at military bases in the balloon’s path as it drifted over the United States.

But the balloon continues to roil relations between the world’s two great powers and largest economies, already at one of their lowest points in decades.

Critical channels of communication have imploded. Wei Fenghe, China’s defence minister, refused to take a phone call from Lloyd Austin, the US defence secretary, soon after the Feb. 4 shootdown, the Pentagon said. Blinken has not rescheduled the visit to Beijing he cancelled during the uproar over the balloon. And the White House and the Chinese Foreign Ministry traded public barbs this week over their spy programs.

Perhaps the greatest long-term impact comes from the impression left with ordinary citizens who have followed the balloon saga, said Yuen Yuen Ang, a China scholar at Johns Hopkins University.

“When public opinion that the other country is an enemy solidifies,” she said, “it becomes ever harder for leaders in America and China to soften their stances and stabilize relations.”

-New York Times