Quite simply the US (and allied) forces did not lose the war in South Viet Nam. A lack of political will and cr@p rules of engagement allowed the other side to have a distinct advantage. Post Tet '68 the VC and NVA in the South were reeling and a spent force. A lack of positive follow up led to a massive troop build up from the North and the rest is history. Similarly today the allies are too soft and politically unwilling to take extremely difficult steps.
GAGS
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