Richardson uses the withdrawal of the last troops from Iraq to summarize the thinking that led us into that disastrous conflict. The invasion of Iraq was not only devastating to that country, but also to Afghanistan which was conquered on the cheap and starved of resources that were diverted to Iraq. With the US trying to stabilize two countries, they stabilized neither. The loss of lives, money and prestige made the Iraq War arguably the greatest foreign policy mistake in US history. At least Vietnam made a certain logical sense within the Cold War and the US rejection of Versailles was in keeping with previous US foreign policy.
Iraq was unnecessary and flawed from the start. It squandered the international goodwill that accrued to the US after 9/11 and exposed the flaws of even the world's most powerful military.
It was the biggest foreign policy disaster until Donald Trump launched a war of choice against Iran with the increasingly archaic military doctrines of Pete Hegseth. I do believe that if the House returned to session, Hegseth gets impeached and the vote wouldn't be close. In fact, I think he gets removed in the Senate.
The primary geopolitical benefactor of Donald Trump's election has been China, then Europe, then Israel then Russia. The primary loser has been the United States.