Funny enough, the CDC just a few weeks ago said wearing a mask won't help, and now they are strongly encouraging it.

Incompetence and attempts to cover their ass.

Masks do help, everybody knows this and so does the CDC. What they needed was for people to not panic purchase PPE so that healthcare workers would not have to compete with the general public for the limited supply.

Now some time has passed, reported infections and deaths are up, and they realize that they need some kind of face covering on people and their time of plausible deniability's up so… Wear a mask, everybody. Whatever they managed to get for the healthcare workers up until that point will have to do.

Also, it's not that people in the US don't wear a mask during regular, even "bad" flu seasons because they don't help… It's because people are stupid and stubborn.

Other countries do have the cultural norm of "you wear a mask when you're sick" along with "you just wear a mask regardless, when it's flu season."

You should wear a mask when you are sick, and you should have been before this year, anyway.

"But I'm not sick!"

One of the key characteristics of the current pandemic is a very long incubation period during which people may remain asymptomatic and still able to spread the disease. Until everybody can test themselves in their home every morning, you don't know whether you're sick or not. So be considerate, and wear a mask.

If it helps you feel better, remember that governments around the world hate masks with a passion, and many of them have passed or tried passed anti-mask laws To help them be able to identify people who take part in protests and other actions that the government doesn't approve of.