The Center for American Entrepreneurship has published a study on the rise of global startups and the decline of American dominance in startup and venture capital activity: http://www.startupsusa.org/global-startup-cities/
Citylab and The Mercury News explore the role America’s recent immigration policies have played in these changes:
https://www.citylab.com/life/2018/10/america-losing-its-edge-startups/572323/
H-1B: As immigration furor roils Silicon Valley, Canada smooths way for techies