This is, no doubt, so that Britain can continue to romance the notion that they head up an EMPIRE.
As an American, with Canadian cousins, I think history shows rarely have two nations shared so much common history, and families. When we say "cousins to the north" we mean REAL cousins, in my family (and great-great grandparents).
Canadian forces train with that as a given.
Canada is expert in Blue Beret jobs (we started them at Suez) so a Canadian brigidier is likely to command a Blue Beret job.
OTOH, in peace restoration work or stabilization work, our units are more likely to be attached to Brit or US units.
The Blue Beret jobs, if properly constituted, consist of only forces from small countries with no dog in the fight between the parties that have invited them in.
The other jobs usually require Brit or US presence, which would be inappropriate in a Blue Beret job, so in those cases it makes no sense for our units to operate independently.
Our units are able to integrate seamlessly with US or Brit forces.
For example, Canadian frigates customarily participate as part of the escort screens for US CVNs.
At Kosovo, our Coyote recce squadron of the Lord Strathcona Horse (Royal Canadians) was part of the Brit sector where the Brits made good use of the capabilities of the Coyotes and their crews.
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