SciFrog:
USA is not big enough a “region” for you? 
Tesla roots are in the USA and their charger network is developed here first. Plus the high price tag of the cars severely kill the sales in many countries, like France or Spain for example. Until Tesla has a bigger lineup, it is totally fair to only look at the markets they actually can sell cars...
China is at 30 million SAAR and growing whilst the States are a stagnant 17 million SAAR. Therefore, the U.S. market pales in comparison and is roughly equivalent to the EU market.
The real question is should Musk try to create a modern day Ford in a highly competitive and ruthlessly efficient industry or should the plan be to remain a niche player striving toward profitability. Musk instead tries for world domination using his “first principles” -really smoke and mirrors-to raise capital that still falls woefully short of levels for the required CapEx to meet the goal.
While a few here are fixated on comparing Tesla to the German Three, Musk’s real target has been Henry Ford and mass production. Musk thinks he brings insight but it’s only his arrogance. Automaking is a difficult and relatively low volume industry with little of the increasing returns-see W. Brian Arthur’s works-found in Tech. Ford remains the leading, and most profitable maker of premium vehicles, as defined by price above $50,000, yet its market cap trails Tesla.