The triangle in question was Canada, the United States of America, and the United Kingdom. This triangle was invisible to Americans or Britons, for whom Canada was a side issue at best, but it was vital to Canada. Canada was intimately involved with both countries, and needed good relations between them for its own security. The primary concern of Canadian governments was to avoid a repetition of the American invasions of 1775 and 1812–1815, when Canada had been used as the battlefield where American and British differences were settled.