Joseph Heller: "It's all fucked up."

what exactly did he mean by the phrase
CATCH-22?
from my lips directly to you:
a Willie Mays center fielder's running grab?
a discovery in the National Institute of Mental Health lab?
Joe avoided a violent military death
wrote a best selling book many years before he drew his last breath
a long, slow, measured exhale
but he got to chase the girls successfully with more than one piece of tail
his B-25, a fine airplane
coming in low and fast, weaving through heavy enemy flack totally insane
it was very sane to want to stay inside an Air Force canvas tent
crazy to fly in formation if that's what he really meant
during WWII, the thin man and the fat
the bald guy and the clown who never removed his hat
the wop and the Jew
who on Sunday morning didn't know how to act or what to do
the black aviator and the brave Mexican from San Diego
neither wanted a tag from graves registration tied to their big toe
and the freckled kid from cold Minnesota
drinking a warm coca cola
between briefings and the next flight
they all felt deep down inside their guts an incredible fright
and wondered more than once if they'd get out in one piece
to become whole again and discovered by a lover and live in peace
Yossarian.  Major Major.  CATCH-22?
it's what they did heroically and awkwardly continue to do.