Shortly after 2.30pm on Saturday afternoon people on the beaches of South Carolina could see contrails in the cloudless blue sky and then hear a dull sound.
A US Air Force F22 fighter had fired a missile at a Chinese balloon that had captivated the United States for the previous several days as it floated diagonally across the country including overflying hugely sensitive military installations.
The balloon collapsed and plummeted downwards from about 18,000m (60,000ft) before crashing into about 14m of water in the Atlantic Ocean.
It marked the end (or at least this phase) of an incident that had brought together politics, diplomacy and espionage.
The US government insisted the balloon was a Chinese surveillance craft on a spying mission.
Beijing argued it was a weather balloon that had strayed significantly off course.
Whatever it was, balloon incident wrecked a long-planned diplomatic initiative aimed at rebuilding relations between Washington and Beijing that have been strained for some time.
Last Friday morning just hours before he was scheduled to leave, the US secretary of state, Antony Blinken, postponed a scheduled visit to Beijing.
The day before, the US military had announced the Chinese balloon was loitering above Montana, where several key nuclear missile installations are based. In the controversy that ensued it would have been virtually impossible politically for Blinken to travel to Beijing.
The secretary of state said on Friday that sending the balloon over US territory was “an irresponsible act and that (China’s) decision to take this action on the eve of my visit is detrimental to the substantive discussions that we were prepared to have.”
The Chinese foreign ministry had expressed “regret” and argued that it was a civilian balloon intended for meteorological research.
In the United States very few in authority were prepared to believe that account.
US defence secretary Lloyd Austin specifically maintained on Saturday that the balloon, was being used by China “in an attempt to surveil strategic sites in the continental United States”.
Chinese spy satellites in space cross over the United States several times each day. And the Pentagon said on Friday that it had “seen this type of balloon activity elsewhere before”.
However, it said what made the balloon episode on this occasion different was “the duration and the length of which it has been over US territory”.
The size of the balloon was also quite large. Beneath it was a payload of solar panels and possibly other equipment. It was reported to be as big as two or three single deck buses.
The US military also maintained the Chinese balloon “has the ability to manoeuvre” – suggesting that it was not simply being blown by the wind.
In addition, once its presence had been publicly announced, the size meant the craft could be seen from the ground.
Footage of the balloon flooded the internet and US news media followed its track as it moved eastward.
The public was concerned. Some under its flight path said in online posts that they would try to shoot it down themselves. Some Republican politicians posted pictures of themselves with guns pointed up towards the sky.
On Saturday, a sheriff’s office in South Carolina warned on Twitter: “Don’t try to shoot it!! Your rifle rounds WILL NOT reach it. Be responsible. What goes up will come down, including your bullets.”
Politically the balloon presented significant problems for the Biden administration.
For some reason many on the right are fixated on China and perceived threats to the US in a way which they are not with Russia, for example.
Hardly a day goes by without some Republican figure making claims about business links between the Biden family and China.
A key Republican message is that the US must be tougher with China.
A series of Republicans contended the balloon incursion made the country look weak. They demanded to know why US president Joe Biden had not ordered the balloon to be shot down immediately.
On Saturday, Biden said that on Wednesday when briefed about the balloon he had ordered the Pentagon to shoot it down “as soon as possible”.
“They decided that the best time to do that was as it got over water.”
Austin said that “US military commanders had determined downing the balloon while over land posed an undue risk to people across a wide area due to the size and altitude of the balloon and its surveillance payload”.
So what are the consequences from the whole balloon affair?
In the first instance the US intelligence is likely to soon have in its possession whatever parts of the balloon and its cargo – including any technology – that survived the fall into the sea.
The US navy and coast guard cordoned off the area immediately. A salvage vessel is expected to try scoop up whatever is found, and this will be brought to a laboratory in Virginia for analysis.
The president will still face strong criticism from his Republican opponents. The balloon may have been shot down but his critics argue this was not done soon enough.
Republicans control the House of Representatives and there may well be hearings to scrutinise the actions of the White House and the Pentagon.
Perhaps more consequential will be the implications for relations with Beijing.
The US openly views China as its main strategic competitor.
The State Department last week described the relationship between the US and China as “the most consequential and complex” on the planet.
Relations between the two powers have been tense for some time, particularly over Taiwan, restrictions on technology exports and security issues.
At a meeting last November Biden and Chinese leader Xi Jinping agreed to keep open lines of communications. The Blinken visit formed a key part of that commitment.
Before the balloon controversy, some US China experts suggested relations might be improving and that Beijing was showing more “something of a marginal course correction to pragmatism” as it sought to address its own internal economic and other issues.
The questions academics, the State department and the White House will now have to consider is if this was a Chinese spying mission, why would Beijing have wanted to undertake it just before Blinken was due to arrive.