Oops, it doesn't look like 'mighty eighth museum air force museum on memorial day' is a national day..

Other days

blanket fort

Blanket Fort Day
lash

Lash Day
unicorn

Unicorn Day
self care

Self Care Day
self appreciation

Self Appreciation Day
coffee

Coffee Day
me

Me Day
my little pony

My Little Pony Day
carpenters

Carpenters Day
boy friend

Boy Friend Day