Who said we'd assume China will defend Canadian interests? The current strategy is focused on growing much closer to the EU while becoming a trade bridge for Atlantic/Pacific relations. Canada has a lot of clout on the international stage so we've been able to match-make trade linkages while expanding our market.

Canada isn't a first rate power - if the US or China decided to unilaterally target us it'd be deeply damaging. The hope is that working in concert with other middle powers we can form a cushion to soften a blow - not fully turn it.