The Obama administration has directed the military to not allow personnel to say “Christmas”, in spite of the holiday’s status as a federally-recognized holiday.
The reason given by armed forces officials is that not everyone celebrates Christmas and that out of respect for them, military members should refer to Christmas celebrations simply as “holiday”-themed festivities.
This prohibition comes in the context of a wider push for political correctness in society in general and the military in particular, as evidenced by the recent reprimanding of Navy Chaplain Wes Modder for simply discussing religion, as chaplains are wont to do, with military personnel.
See how servicemen have reacted to not being allowed to say Christmas at the link below:

Pathetic
Do you people need to believe this? Does it make you feel better somehow. I dont understand the need to feel attacked and why there is a concerted effort to make a group feel attacked. What motivates such lies? Who does these sort of lies help?
NS!!!
Shame on Obama Impeach him already!
Merry Christmas
I, a citizen of The United States of America, am calling for the arrest and trial of Barack Hussein Obama for treason, under Article 3 of the United States Constitution for aiding and giving comfort to our enemies… If you agree, please copy and repost!!!
This man should be removed from office
This is bull c**p. We are United States citizens and if we want to wish someone Merry Christmas we will. Obama needs to worry about how much he offends Americans instead of worrying about other people. This is America. He was placed in office by Americans. However they were misled by him and the Democratic Party.
Merry Christmas to all!
Why hasn’t he been murdered yet