Thank God I'm A Country Boy - John Denver
Pledge Allegiance to the Hag - Eric Church (a.k.a. "Pledge Allegiance to the Flag")
Cowboys Like Us - George Strait
Heartland - George Strait
Three Wooden Crosses - Randy Travis

And my personal fave, which was written/sung by a country singer but is not really "country" at all: Ireland, by Garth Brooks.