The tunnels were later used Using as a staging area for the attack Attack on Saigon during the 1968 Tet offensive Attack before they were largely destroyed Destroying by heavy bombing Attack from American B-52 bombers in 1970 , ending Process_end their utility .

American and South Vietnamese intelligence reports Reporting had indicated Statement that an imminent communist offensive during the Tet New Year festival was likely , and in response Response the Australians and New Zealanders were deployed Arranging away from their base in Phuoc Tuy Province to bolster American and South Vietnamese forces defending the Long Binh–Bien Hoa complex north-east of Saigon .

Meanwhile , the remaining Australian forces in Phuoc Tuy Province also successfully repelled Defending repeated Viet Cong attacks Attack against Ba Ria and Long Dien , as part of the Tet Offensive that had engulfed population centres across South Vietnam .

The Tet Offensive of 1968 showed Presence the lack of progress with these doctrines as the NLF and PAVN mounted Connect large-scale urban offensives throughout 1968 , turning US domestic support against the war .

The Army of the Republic of Vietnam ( ARVN ) expanded Expansion following a period of neglect after Tet , modeled on US doctrine .

The NLF sustained heavy losses during the Tet Offensive , losing over half its strength in a matter of months , which combined with subsequent U.S.-ARVN operations in the rest of 1968 , nearly wiped out the southern insurgency .