U.S. troops fly over northern Afghanistan in the early days of the war in 2001. The U.S. fought its longest ever war in Afghanistan, for 20 years, only to see the Taliban retake control of the country as the U.S. withdrew in 2021. Brennan Linsley/AP pool/AFP via Getty Images hide caption toggle caption Brennan Linsley/AP pool/AFP via Getty Images The U.S. has been at war for more than 20 of the past 25 years in three major conflicts all in the same region. First, Afghanistan, then Iraq, now Iran. U.S. presidents said overwhelming American miliary firepower would decide all these wars swiftly. Under President George W. Bush, the U.S. military needed just weeks to oust the Taliban in Afghanistan in 2001 and President Saddam Hussein in Iraq in 2003. Under President Trump, the U.S. bombing campaign, assisted by Israel, killed many of Iran's leaders on the first day of the war and hammered the country at will.…