In 2001, a month after the September 11th attacks, the US invaded Afghanistan in Operation Enduring Freedom. The goal was to remove the Taliban from power and to dismantle al-Qaeda. While successful in removing the Taliban from power, most al-Qaeda fighters fled to Pakistan.

During the war, over 26,000 civilians not involved in the fighting were killed as a result of war-related violence, and 29,900 were injured. 91,000 Afghan civilians and soldiers died in the conflict. As of 2013 there are 2.2 million refugees who have not yet returned.
The initial air campaign in Operation Enduring Freedom had sparked protests due to the number of civilians killed.

Although Christianity is the largest religion in America, Islam and Judaism are both growing at a fast pace.

In 1978, a group allied with the USSR had gone into Afghanistan and set up a communist government. The US was upset by this and started to supply weapons & money to the mujahideen, who fought against the USSR.
While much of Afghanistan was originally against the mujahideen, they threw their support behind them when the USSR launched a full-scale invasion of Afghanistan.
Due to the loss of territory in Afghanistan and the high cost of the war, USSR eventually withdrew its forces from Afghanistan in 1989.

Hamid Karzai was the first Afghanistan president to be elected democratically. He had wanted to make Afghanistan more of a democracy, which made the US very happy. The two have worked closely for a few years.

Rumors were spread that Karzai and his staff were paid by the CIA, which later proved to be true. This fact, along with suspicions of corruption within the government, made Karzai initially unpopular among the Afghanistan citizens. Eventually, they warmed up to him.

In 2014, the Afghanistan government released 65 prisoners that the US had placed into prisons. They had been arrested for suspected terrorist activities, but the Afghanistan later released them without the permission of the US. The US was upset by this.

In Afghanistan's defense, there was a lack of evidence to tie all 65 prisoners to terrorist activities. They had been in prion for years without a trial, which President Karzai thought was very unfair. Due to this, they had to release the prisoners.