TOKYO -- The Taliban's lightning return to power in Afghanistan raises the prospect that the ungovernable country will again become a hotbed of Islamic extremism.
Why then did the U.S. -- which more than any country on Earth should have seen this possibility -- push ahead with its speedy drawdown of troops after a 20-year military adventure?
"We've succeeded in [our] mission, and in fact, we succeeded a while ago," said U.S. Secretary of State Antony Blinken in an Aug. 15 television interview.
Blinken said the capitulation of Kabul, the Afghan capital, does not compare to the fall of Saigon in South Vietnam when Indochina was finally overrun by communist forces in 1975.
"Over those 20 years, we brought [Osama] bin Laden to justice, we vastly diminished the threat posed by Al-Qaeda in Afghanistan to the United States -- to the point where it is not capable of conducting such an attack again from Afghanistan," he said.
President Joe Biden's vision of the U.S. national interest -- eliminating the threat of terrorist attacks on U.S. soil -- is evidently different to that of the Republican administration of President George W. Bush, which took up arms to punish terrorist aggression in the wake of 9-11 and to democratize Afghanistan and the Middle East.
The U.S. has paid a high price for what little may endure from its presence. More than 2,300 U.S. soldiers have been killed in a land that has for centuries been the reputed boneyard of empires. The aid-dependent Afghan government has meanwhile never become self-reliant, and corruption and infighting have been rampant.
"If Afghanistan is unable to mount any real resistance to the Taliban now, there is no chance that one year -- one more year, five more years or 20 more years of U.S. military boots on the ground -- would have made any difference," said Biden.
The fall of Kabul has so far not shaken the U.S. determination to withdraw. Troops are being pulled out on the basis that sufficient objectives have been met.
In 2011, U.S. special forces killed bin Laden, the founder of the Al-Qaeda international terrorist network and mastermind of the aerial attacks on the U.S. in 2011. His killing in Pakistan was fully 10 years ago, so what has changed since?
Al-Qaeda is certainly not the same without him. By the morning of Aug. 17, Al-Qaeda's leadership had made no comment on the Taliban's retaking of Kabul, noted Shuji Hosaka, director of the Japanese Institute of Middle Eastern Economics at Japan's Institute of Energy Economics.
"This is not the only time that Al-Qaeda's ability to issue rapid responses has diminished," Hosaka told Nikkei Asia.
Al-Qaeda was once a military arm of the Taliban and the pair often coordinated operations. One would therefore have expected Al-Qaeda to come out immediately to welcome the historic retaking of Kabul.
Bin Laden was succeeded as Al-Qaeda leader by Ayman al-Zawahiri, an Egyptian doctor whose movements have been hard to track. Last year, it was even rumored that he had died.
Last August, a senior Al-Qaeda figure was assassinated in Tehran, and there were unconfirmed reports that it was a hit by Israeli intelligence.
Hamza bin Laden, a son of Osama, was also rumored to be dead, but without any information on when and where he was killed.
After bin Laden was taken out, the war on terrorism continued under the radar. It is thought that over 10 senior members of Al-Qaeda-affiliated organizations have died in recent years.
It is not surprising therefore that analysts have concluded that Al-Qaeda attacks on the U.S. mainland are unlikely, removing one block to a U.S. withdrawal.
A question that now arises is whether the U.S. got the peace talks wrong by negotiating directly with the Taliban without the Afghan government present. In return for the withdrawal of U.S. troops, the Taliban promised to engage in dialogue with the Afghan government -- and not to allow terrorist organizations to use Afghanistan as a base for attacks on foreign countries.
The problem with the withdrawal terms is U.S. dependence on the sincerity and capability of the Taliban.
Some observers do believe that the Taliban has become more moderate since being ousted by the U.S. Taliban leaders presented themselves as the only ones to talk to, but they have already reneged on their promise to negotiate with the Afghan government for a peaceful transfer of power. Kabul is already in their hands.
There is no guarantee that the Taliban will keep its promise and ensure that Afghanistan will not be used as an operating base by international terrorists. Indeed, if Afghanistan falls again into chaos under Taliban rule, terrorist organizations will find its ungoverned pockets a natural breeding ground.
And while Al-Qaeda might have been weakened, its radical ideology has nurtured other groups. Islamic State, a still active militant group that visited multiple inhumanities on Iraq and Syria, is a "mutant" derivative of Al-Qaeda.
"Whether Afghanistan becomes a hotbed of terrorism or not depends on whether the Taliban can control all the country," said Hosaka. "If it can't, then forces defeated elsewhere that have nowhere to go will flow in."
The fate of Afghanistan may come back to haunt the U.S. Depending on what happens with the Taliban -- known equally for its zealotry and unreliability -- the world's most powerful military might yet be dragged back into something more incendiary.