You forget that Delta was first identified in India. Lambda (or whichever) was first identified in South Africa. I’m sure there will be an American variant, but it’s not just antivaxxers continuing this on... Biden and the other leaders are trying to help by shipping doses, but getting them in arms is an issue. 

That was an inconclusive tweet at best, while his vague, non-answer should be taken for what it is: tacit approval.