| Operation Hardihood | |||||||
|---|---|---|---|---|---|---|---|
| Part of Vietnam War | |||||||
 5RAR soldiers guard Vietnamese civilians | |||||||
| |||||||
| Belligerents | |||||||
 United States Australia |
 Viet Cong | ||||||
| Commanders and leaders | |||||||
|
BG Paul F. Smith |
| ||||||
| Units involved | |||||||
|
503rd Infantry Regiment 1st Battalion, Royal Australian Regiment 5th Battalion, Royal Australian Regiment | D445 Provincial Mobile Battalion | ||||||
| Casualties and losses | |||||||
|
23 killed 5 killed | US body count: 48 killed | ||||||
Operation Hardihood was a security operation conducted from 16 May to 8 June 1966 during the Vietnam War by the U.S. 503rd Infantry Regiment, the 1st Battalion, Royal Australian Regiment (1RAR) and the 5th Battalion, Royal Australian Regiment (5 RAR) in Phước Tuy Province, South Vietnam to secure the area around Nui Dat for the establishment of a base area for the 1st Australian Task Force (1 ATF).