I wouldn't argue that masks are a political dividing line, although 'fashion statement" is not a factor to be ignored either. I live in northern VA, 10 miles from the White House, and about 1/3rd of people in the local grocery stores don't wear masks, that's about the same fractions as workers in the stores.
I was in MD a few miles outside the DC line this weekend, and caught alot of dirty looks for not wearing a mask, also, I committed the mortal sin of pushing the siliver buggy in the wrong direction against the one-way markers on the aisles. They don't exist in NoVa and I frankly didn't notice them, so I guess said, "Oops, sorry (Like I give a shit, nimrods)".
So, that's what a difference of six miles, going from one state to another makes...
I do cancer research sort of as a hobby so I get all the articles on covid emailed to me directly, whether I ask for them or not. It's not clear that masks do any good, and might do actual harm. Having said that, before someone calls me an idiot, I'll say that, yes, I could be wrong, but I'm not the only MD who has reached this opinion....
In the OR, your Friendly Neighborhood Surgeon & Co. wear masks, not for filtration, but to avoid one's breath going directly into the wound.
Viruses are really small. Filters good enough to isolate them didn't exist until the 1960s, to give you an idea. A mask is not going to filter viruses or bacteria very well at all,
But, they will do a fair job of filtering droplets from sneezes and coughs that contain the germs. The problem is:
Once that stuff has been caught by the mask, you're re-inhaling it, thousands and thousands of times. That equals re-infection, unless you're changing your mask quite frequently. (It's not really well understood, but the size of droplets has a big effect on whether they just get inhaled and exhaled with no harm done, or get caught in your nose(usually not a big deal), or end up snagged deep in your lungs (problem) ).
So, a mask probably helps some in your not spreading the germs to other people, although I suspect unless your coughing in someone's face the effect is likely minimal.
However, once your mask has snagged germs, from something you've inhaled yourself or droplets from someone else who coughed near you, you're re-infecting yourself. Once those germs are multiplying in your system, you're a spreader, and probably going to get sick yourself.
I've read scientific publications not generally accessible to the public unless you know where to dig the journals up, and I haven't read a single thing that makes a really solid case that masks do any net good. Again, I'm not talking about an OR situation where it's a confined space and everything is discarded after one use. I'm talking about the local grocery store and a mask that's reused many times.
I personally have decided that not to use a mask. I think that's best for me and others around me. If I was to go into a nursing home, or any place with close quarters, etc., then like in an OR a mask is a good idea.
This whole thing is a case where the science is overlooked in the interests of infotainment, or half assed political agendas, if you ask me. Just my opinion, but I think it's based on solid analysis....