2019 Canada To 1979

  Going to be a hell of a lot of butterflies.  Too late to prevent the Iranian revolution, or very likely to stop it being derailed by Khomeini and his fellow fanatics.  Ditto unfortunately with Thatcher in the UK.  However does enough news leak out to deter the Soviets from going into Afghanistan [unlikely I suspect] or possibly escalate matters further.  Can Reagan's rise be prevented in the US?

  Plenty of potential for technological steps forward and earlier efforts to prevent pollution.  Doubly so if the post-war consensus in the UK/US isn't replaced by a conservative reaction.  Will still be a lot of inertia on a lot of issues but a decent possibility that things will be better and changes come faster. 

  Also going to be a lot of secrets exposed which could end a lot of political careers and also have dire consequences for a number of public figures.  You might see an earlier reform of the Catholic church in terms of pedophilia cases - although again there is likely to be a hell of a lot of denial and resistance to overcome 1st.

  Not sure what the west will do - or wish to do - to prevent some of the violent events of the last 40 years, possibly especially in the rise of Islamic extremism and how successful that might be.  How both they and the Soviets will respond to the predicted collapse of the latter.

  That is a possibility, especially once they a) realise that this is actually the case and b) hear details of the collapse of the Soviet empire.  Alternatively this might prompt them to hunker down perhaps with some attempts to reform.  Brezhnev is getting towards his last years, dying in 82 OTL but might be replaced earlier.  The question is would they go double or quits and select a hard liner or look to reform?

  The other potential problem might be the rest of the Soviet empire.  Its shortly before the Solidarity demonstrations take off in Poland and when the eastern European states learn that they 'will' become independent in the near future there's likely to be a lot of unrest.  Along with what might happen in places like Ukraine, the Baltic states, the Central Asian SSRs etc.  If so does things collapse very quickly or it get very, very bloody, either just within the empire or possibly expanding to an attack on western Europe?

  In the event of a wider war then 2018 Canada's military forces are likely to play a minor role at most as their too small.  Likewise a lot of their technological capacity in the short run might be crippled by the disruption of loss of connections to their 2018 trade partners.  However they would likely be very, very useful in terms of intelligence processing and possibly historical [for them] information about Soviet weaknesses and characters.

  That would be nasty but what I'm really fearing is that a hard liner group makes a do-or die bid for western Europe.  They can probably take the continent, even without the use of nukes or chemical weapons, although what happens when they reach the French border or what NATO does in response could be very explosive.  Easily escalate into the nightmare scenario of an all out nuclear exchange.