I think that POTUS is laying the foundation to declare a national emergency and cancel the 2020 election.
Whitmer: Masks encouraged, but will not be required, for in-person voting
Voters will not be required to wear a mask if they decide to enter a polling place to cast a ballot, Gov. Gretchen Whitmer said Friday.
https://www.freep.com/story/news/politics/2020/07/17/whitmer-masks-required-voting-poll-election-day/5460604002/