U.S. says it won’t join WHO-linked effort to develop, distribute coronavirus vaccine - The Washington Post

...Experts in health security see at least two problems with this strategy: The first is that a new vaccine is unlikely to offer complete protection to all people, meaning that a portion of the U.S. population will still be vulnerable to imported cases — especially as tourism and trade resume. The second, related problem is that a U.S. recovery depends on economic recovery elsewhere. If large parts of the world are still in lockdown, the global economy is smarting and supply chains are disrupted, the United States will not be able to bounce back...
https://www.washingtonpost.com/world/coronavirus-vaccine-trump/2020/09/01/b44b42be-e965-11ea-bf44-0d31c85838a5_story.html