Agreed that a skirmish could lead to a larger engagement, but we fought Vietnam with one hand tied behind our back as walking on egg shells trying not to piss off the Soviets. He talks about Iraq 2003 which was a massive intelligence failure, but we went for the jugular right away, not the same, but people always wanted the comparison. The lessons learned from those previous Wars are not lost on people in the Pentagon or in the intelligence services.
People use Vietnam as a rallying cry just like they think the Right war mongers by warning about security concerns. They both are very excessive .