If thats the case they should have used a black ribbon...
Blue symbolizes things that seem unrelated to this tragedy where black symbolized mourning and was used to remember previous massacre.
http://www.trinitylondon.com/awareness-ribbon-meanings.asp
http://en.wikipedia.org/wiki/List_of_awareness_ribbons
Blue Ribbon :
Meaning: This color is a symbol of drunk driving, child abuse, Osteogenesis Imperfecta (OI), the victims of hurricane Katrina, dystonia, acute respiratory distress syndrome (ARDS), alopecia, Education, Epstein-Barr Virus, Save the Music, colon cancer (alternative ribbon color: brown), colorectal cancer (alternative ribbon color: brown), and anti-tobacco - particularly anti-second hand smoke (in Canada; alternative ribbon color: brown), I Love Clean Air/ILCA Campaign (Japan)
What are you referring to?