The outgoing president won't wear one much, the incoming president wears one much of the time: a mask to guard against the spread of COVID-19.
The medical became political in America, but that's not the only place Dr. Ralph Eccles directs his attention. The retired endocrinologist from Klamath Falls studies the pandemic and remedies, and has a lot to teach about masks.
One example: a bandana stops working after a little while. Listen for the reasons.