Chaotic scenes of Afghans trying to flee their home country after the Taliban’s takeover are shocking indeed. The Taliban swept into Kabul, Afghanistan’s capital, Sunday after the government collapsed. As the insurgents closed in, President Ashraf Ghani fled the country.

Afghanistan was taken back by the Taliban nearly 20 years after the US declared a war on terror then entered Kabul in November 2001.

Though Afghan government forces had more than 300,000 soldiers and equipment that was more advanced than the Taliban arsenal, they appeared powerless in the face of much fewer Taliban rebels.

As the Taliban returned, thousands of Afghans desperate to flee thronged the airport in Kabul. In video footage, people clung to the exterior of a US military plane as it taxied on the runway.

US President Joe Biden spoke from the White House on Monday about the US withdrawal from Afghanistan: “I will not repeat the mistakes we’ve made in the past. The mistake of staying and fighting indefinitely in a conflict that is not in the national interest of the United States, of doubling down on a civil war in a foreign country, of attempting to remake a country through the endless military deployments of US forces.”

The United States poured $83 billion over two decades to build and train Afghan security forces after breaking down the Taliban regime. It even supplied modern military equipment.

Afghan government leaders should have beefed up their military to protect their people from Taliban attacks. But the opposite happened.

On paper, the Afghan army was better equipped and outnumbered the estimated 70,000-strong Taliban, but a significant number of government troops reportedly were “ghost soldiers,” nothing but “fake personnel records that corrupt actors used to pocket salaries.”

From a realistic standpoint, it would have been unacceptable to keep pouring water into a sieve.

The corruption of the ruling class, the breakdown of military discipline and the lack of popular will to defend their country hastened the quick fall of Afghanistan.

“American troops cannot and should not be fighting in a war and dying in a war that Afghan forces are not willing to fight for themselves,” Biden said. This remark exudes his deep disappointment. It is reasonable, but it sounds unusual to an ally such as South Korea. It is hard to expect America to keep fighting indefinitely for a country unwilling and unprepared to fight for its freedom and democracy.

The administration under President Moon Jae-in should look at the crisis in Afghanistan as an opportunity to look back on how it has treated the US alliance.

Despite the North’s escalating nuclear threat, the Moon administration has shown a submissive attitude toward North Korea and its ally China, straining the US alliance.

Kim Yo-jong, the sister of North Korean leader Kim Jong-un, recently demanded the joint South Korea-US military exercises be scrapped, and the Moon administration chimed in, scaling them down. The drills have become unsubstantial.

She went further to demand US troops withdraw from the South. Some civic and labor groups in the South publicly voiced the same demand. A spy ring carried out an operation to incite popular protests against the deployment of antimissile systems and even tried to infiltrate the ruling camp. Sexual harassment scandals dogged the military, revealing poor military discipline.

South Koreans have built their nation and developed it on the bedrock of the US alliance after Korea was liberated from Japanese colonial rule. The US alliance is also the pillar of South Korea’s national security. Without it, it is questionable if the South alone can fight off North Korea’s invasion, which will likely be backed up by China.

If South Korea becomes more of a burden to its ally rather than being economically or militarily valuable, its alliance can break down anytime. An everlasting alliance does not exist for a country who is neither willing nor trying to defend themselves. From now on, the administration should tighten its security posture and try to further strengthen the US alliance.