Well, there is a difference: When Saigon fell it was despite the efforts of our South Vietamese allies to resist, and resist they did, even through in the peace accords that allowed our exit called on us to provide air and naval support in the event the NVA invaded the South after our withdrawal, which part of the agreement we shamefully reneged on. When Kabul fell our allies offered no resistance, at least in part because the "democratic" government was really a kleptocracy that stole the rations and the ammunition they would have needed to offer resistance -- there is no other explanation for the reports of the Afghan Army having neither food nor ammunition.
