This
database is a comprehensive collection of all the American idioms and slang available.
American Idioms are many and varied. We hope you enjoy our collection. We are adding more all the time.
.
If someone wraps themselves in the flag, they pretend to be doing something for patriotic reasons or out of loyalty, but their real motives are selfish.
('Drape yourself in the flag' is an alternative form of this idiom)