Yes, today is the day we should honor them!
http://www.militarycity.com/valor/honor.html
I was wondering which flag to use for this, so I looked it up. It IS a half-mast display day. "There are four specific occasions during which the flag of the United States is flown at half-staff, or at the mid-way point of the staff or pole to which it is attached:
Memorial Day
Peace Officers Memorial Day
At the Direction of the President
At the Direction of a State's Governor"
..one thing I miss not being in the U.S., going to the services at Memorial Park!