Now we see the real reasons for Joe Biden's visit. He was Obama's emissary for:

1. A treaty banning drilling in arctic waters - one that the incoming president can not easily reverse.

2. The co-opting of Canada into a show of belligerence in Latvia. The border of Russia is already bristling with NATO missiles and defensive weapons. This provocation is unnecessary and only serves to further destabilize the region.

Both of these are Obama's "up yours" to the incoming president. Obama has been no friend of Canada during his eight-year presidency. Only now does he court Trudeau, who in his inexperience has given the finger to both the USA and Russia. Trump has clearly signalled that he wants to thaw relations with Putin, but after a few hours of flattery by Joe Biden, Trudeau has been persuaded to do exactly the opposite. 

Obama will be gone in a few weeks, but Trudeau will remain to deal with the consequences of this deliberate provocation. Neither Trump nor Putin will forget.