Um...Hitler's birtday was the 20th of April, I had a boss that shared a birthday with him, a quick web searc will confirm this. Today is Jedi day, you know 'May the 4th be with you'.
But think it through...do people really appreciate a Hitler joke or somebody 'saying happy birthday Hitler' sometimes it can seem tasteless. Especially as people still look back at the holocaust with shock and awe and are still effected emotionally by it.
I think the fact it's offensive should be fairly obvious. Some jokes are too offensive to be said or too distasteful or simply something that not everybody could appreciate. I'm sure my butt would be handed to me on a platter if I joked about black-slavery or the genocide that happened in Rwanda or terrorism. Imagine a thread titled: "It's Saddam's Birthday". Reflect on how tasteless that might be.
Though bare also in mind, I'm not saying 'you can't joke about these things' either, it'd make me a hypocrite (my general view of satire is 'anything can be made a target' for it to be fair), but there's tasteful and tasteless, a right place and a wrong place, a right time and a wrong time.
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