Just one day of honorable service during a congressionally determined war era:
It has been this way ever since the formation of the Legion in 1919. The feeling is that all those who take the oath of service immediately assume a risk to themselves, and that they are thus all equally deserving.
This means that servicemembers currently on active duty are certainly eligible to be members. Visit www.legion.org/join to read about the great reasons to continue your service as part of the Legion.