During the initial invasion, US and UK forces bombed al-Qaeda training camps, and later working with the Northern Alliance, the Taliban regime came to an end. In December 2001, after the Taliban government was overthrown, the Afghan Interim Administration under Hamid Karzai was formed. The International Security Assistance Force (ISAF) was established by the UN Security Council to help assist the Karzai administration and provide basic security. By this time, after two decades of war as well as an acute famine at the time, Afghanistan had one of the highest infant and child mortality rates in the world, the lowest life expectancy, much of the population were hungry, and infrastructure was in ruins. Many foreign donors started providing aid and assistance to rebuild the war-torn country. Taliban forces meanwhile began regrouping inside Pakistan, while more coalition troops entered Afghanistan to help the rebuilding process. The Taliban began an insurgency to regain control of Afghanistan. Over the next decade, ISAF and Afghan troops led many offensives against the Taliban, but failed to fully defeat them. Afghanistan remained one of the poorest countries in the world because of a lack of foreign investment, government corruption, and the Taliban insurgency. Meanwhile, Karzai attempted to unite the peoples of the country, and the Afghan government was able to build some democratic structures, adopting a constitution in 2004 with the name Islamic Republic of Afghanistan. Attempts were made, often with the support of foreign donor countries, to improve the country's economy, healthcare, education, transport, and agriculture. ISAF forces also began to train the Afghan National Security Forces. Following 2002, nearly five million Afghans were repatriated. The number of NATO troops present in Afghanistan peaked at 140,000 in 2011, dropping to about 16,000 in 2018. In September 2014 Ashraf Ghani became president after the 2014 presidential election where for the first time in Afghanistan's history power was democratically transferred. On 28 December 2014, NATO formally ended ISAF combat operations in Afghanistan and transferred full security responsibility to the Afghan government. The NATO-led Operation Resolute Support was formed the same day as a successor to ISAF. Thousands of NATO troops remained in the country to train and advise Afghan government forces and continue their fight against the Taliban. On 19 February 2020, the US–Taliban deal was made in Qatar. The 2020 US–Taliban deal was one of the critical events that caused the collapse of the Afghan National