You're welcome, but...
I've heard several expressions, personally and generally, of thanks for my service in the US Army today. I appreciate that, of course, but I can't help thinking that the best way to express appreciation to veterans is to stop sending the active duty troopers to missions unworthy of their service.
Mine was probably the last generation raised to believe that military service wasn't a sacrifice, and certainly wasn't a matter of heroism, though some did serve heroically. We were raised to believe that doing your time, either voluntarily or when called, was an obligation of citizenship. My dad and three of my uncles served in the Pacific theater during World War II. Three more uncles served in the European theater. The cost they paid ranged from a lost leg (Uncle Bill) to malaria (Dad). They all saw active combat. None of them considered themselves "heroes."
My brother preceded me in Vietnam, and if you suggest his Purple Heart is a badge of heroism, he'll laugh at you.
We all served honorably. Heroically? That's someone else's call.
We served, though, and if you appreciate that, well, you're welcome. But, please, don't make any new heroes on our account, unless it's in circumstances where the need to serve is so obvious that thanks become superfluous.
And to all my comrades of every service in every era, welcome home.