I can give you some good examples. Denmark, Norway and even Australia have established expanded committees on national defence, where party leaders participate alongside committee members. This makes a broader kind of consensus possible, and everyone contributes to the creation of a defence policy. That provides an element of security for the future, regardless of the next government.
I think Canada should explore that model more. It has to find a way to institutionalize it, as that's exactly what our allies have done, and it works very well.