He was a member of the Armoured Corps in 1940–45, and saw service in Egypt, Cyprus, the Middle East, New Guinea and New Britain.
He followed his father's footsteps into the NSW Legislative Assembly, where he represented the electoral district of Wollondilly from 1938 to 1949.
In the lead-up to the 1972 federal election, Bate lost Liberal preselection in Macarthur to Max Dunbier, a former state MP.
[7] He decision to stand against an endorsed Liberal candidate resulted in his party membership automatically lapsing.
[9] Bate was married three times: in 1928 to Gerta Ellen Homburg (1907-1985) (two children, John and Margaret); in 1958 to future Country Women's Association president Thelma Kirkby;[10] and on 19 February 1969 to Dame Zara Holt, the widow of Prime Minister Harold Holt.