In my opinion, it's pretty clear that the next three games go to Europe, Africa and Asia in one order or another. Why:
- The European dominated IOC brings the games back to Europe every 2nd to 3rd cycle. That means 2020 or 2024 is Europe's
- The IOC is unlikely to deny a South Africa bid, unless the World Cup goes awry. That means 2020/4 is South Africa's if they bid
- By 2028, it will be 20 years since an Asian Games, and more than 60 years since a Japanese SOG. So, at the latest Tokyo gets 2028.
So, the earliest date for a feasible North American bid is 2032. So, Toronto should probably do a warm-up bid for 2028, and then go all out for 2032.