Post war, from 1946 until 1969, saw what was, probably, the most significant modernization of Canada's military in all history ~ and that was a solidly Liberal achievement. About all we got, new, in the Diefenbaker era, was an austerity programme that featured ball point pens on which was printed "Misuse is abuse, you can help to reduce costs."
Under St Laurent, especially, Canada changed its compete military philosophy, going from a tiny regular force that relied on a large militia, whose capability was entirely mythological, to a larger, highly professional, adequately equipped regular army with a small reserve to provide a mobilization base.
All that changed in 1969 when a new kind of Liberal, Pierre Trudeau, wanted to (I believe was only prevented from by a cabinet revolt) disarm Canada, completely. He is dissuaded and we cut our NATO contribution in half and began the hasty and steady decimation of the Canadian Forces.
Conservative Brian Mulroney may have wanted to rebuild some of our military strength but he and his government were blindsided by the events of the late 1980s and early 1990s when their strategic vision was firmly focused on the 1960s.
Jean Chretien was Pierre Trudeau lite ...
Stephen Harper also, I think, wanted to rebuild but he was ignored by a weak minister (Peter MacKay) who was the captive (sort of political Stockholm Syndrome) of an intellectually empty defence staff who were much more interested in self aggrandizement than the defence of the realm.
Justin Trudeau is, well ... this is a military board.
As a general rule the Liberals were the "military party" from 1947 until 1967. The military didn't like Mackenzie King, and the feeling was mutual. Pierre Trudeau changed that, and a lot more ... and Canadians, a substantial majority of Canadians if what I was told by both Conservative and Liberal insiders was correct, agreed with him. We were, by 1967, simply tired of being a "grown up," "leading middle power," we wanted to spend our clearly visible wealth on ourselves, not on defending Europe and South Korea and heaven alone knows where else. We were even tired of "keeping the peace," because it cost money.
I think ~ personal opinion ~ that the Mulroney and Harper Conservatives were only moderately pro-defence because the Trudeau and Chretien Liberals were so seriously anti-defence; in their heart-of-hearts the Conservatives agreed with the national consensus which Pierre Trudeau recognized and nourished.
