The US military is a giant corporate boondoggle and hit men for the fossil fuel industry, but it's politically important that America's self-perception as the world's unstoppable hyper-power never be deflated by actual events.
Biden's cardinal sin for some people was withdrawing from Afghanistan -- even though Trump negotiated and agreed to it -- because it forced people to reckon with the fact that decades of war had accomplished absolutely nothing except a price tag and a body count.