In the United States, the last Monday of May is set aside as a Federal (National) holiday called Memorial Day. Originally called Decoration Day, it was created to honor those men who had died during the US Civil War. After World War I, the day was changed to honor all those American men and women who died in defense of our country. I can't speak for the entire world, but I know that some other countries have similar days or events.
It may seem presumptuous to compare actual heroic sacrifice to comic book characters. However, unlike most characters in comics who "die" and then "get better," in the pages of The Legion of Super-Heroes most characters who have died stay dead (atleast in their specific continuities.)
We mean no disrespect in calling out these "dead" comic-book characters. In fact, we mean just the opposite. Each of these Legionnaires died in battle, saving the lives of their friends as well as countless others. That is a heroic ideal that we believe all of us can aspire to....and why so many of us actually LIKE these characters and consider them as role models.
All Gave Some
Some Gave All
Remembering Those Who Paid For Our Freedom....