last one in 1991 I believe
The parade was the largest military celebration since the end of World War II. Such displays typically follow a military victory, Dan Lamothe points out for The Washington Post. Without victory, or even a clear cut end to engagement, there haven't been national parades commemorating the wars in Korea or Vietnam, or parades to honor veterans of the wars in Iraq and Afghanistan.
Read more:
https://www.smithsonianmag.com/smart-news/how-military-parades-us-have-changed-180968102/#29A7BevKWQwVoEUX.99