Canada has strong ties with Israel at the geopolitical level, with many interactions concerning security and crowd control mechanisms, as well as military technology trade. It would not be too wildly speculative to think that Canada has received comments from Israel to drop the rhetoric when it comes to Russia's actions.
Harper has said he will oppose Russia until Crimea is returned to Ukraine. Netanyahu has never indicated any interest in Ukraine, and obversely, could just as well operate with Russia as the Middle East's new super power partner as the geopolitical power of the U.S. declines.
Two dogs not barking at this obvious incursion into their direct spheres of interest. This is a good case of 'time will tell'. I do not like being speculative, but truly the silence is deafening.
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