He joined the New Zealand Expeditionary Force (NZEF) and served in the Gallipoli Campaign, during which he received the Distinguished Service Order.

He was evacuated from Gallipoli due to sickness and repatriated to New Zealand, where he saw out the war as an instructor in NZEF training camps.

During the Second World War, Waite was overseas commissioner for the National Patriotic Fund Board and was appointed an Officer of the Order of the British Empire for his services in this role.

[3] Following the outbreak of the First World War in the summer of 1914, Waite volunteered for the New Zealand Expeditionary Force (NZEF) that was being raised for service overseas.

He also undertook to send dispatches from the front for his previous employer, the Otago Witness, but this work proved short-lived when he became a censor as part of his military duties.

[1] He was awarded the Distinguished Service Order,[5] the citation reading: For gallantry and devotion to duty in connection with the operations at the Dardanelles (Mediterranean Expeditionary Force).

On the night of 2–3 May 1915 during the operations in the neighbourhood of Gape Tepe for gallantry and resource in rallying his men, and leading them forward at critical moments.

[1] He remained a member of the TF for several years and was a major in the Otago Mounted Rifles Regiment before being promoted to lieutenant colonel and becoming its commander from 1927 to 1930.

[1] He first stood for election to the House of Representatives in 1925, when he defeated the incumbent in the Clutha electorate, John Edie of the Liberal Party, with ease.

[10][15] Prime Minister George Forbes had not made appointments to the Legislative Council since 1930, with the exception of James Parr in 1931, and membership dwindled during the years of the Great Depression.

[20] While The National News performed an important function during the party's formative years, the venture was expensive and following the 1938 election, it was changed to a quarterly schedule, before being discontinued in September 1939 just after the outbreak of the war.

[21] The seven-member Dominion publicity committee, of which Waite was a member, engaged three advertising companies to jointly prepare for the 1938 election.

[23] He finished the war a colonel, working in Europe on the repatriation of New Zealand personnel recently released from prisoner-of-war camps in Germany.

In 1946, he travelled to Japan to inspect the infrastructure set up for J-Force, New Zealand's contribution to the British Commonwealth Occupation Force, following which he retired from the military.