Bullcrap. Do a simple Google search, and the first two items mention blood libel as usually applying to Jews, but not always.
The term more recently has gained much broader use, exactly because of incidents like this.
I know that google can give different people different results.
But in my search for “blood libel” on Google, the first was the wikipedia entry, which describes it as a specific false accusation of killing for religious sacrifice, made “almost always” against Jews.
The second says it is “the accusation that Jews murder Christian Children”.
The third says “The blood libel is something anti-Semites have historically used in Europe as an excuse to murder Jews”
The fourth set are the news stories about Palin, then some twitter responses to Palin.
The next non-Palin reference links to a page titled “Christian myths against Jews”.
And the next non-Palin reference is Answers.com, to a page headed “Encyclopedia of Judaism: Blood Libel” which starts with: “(also “ritual murder”). False allegation that Jews used the blood of slain Christian children for ritual purposes”
So I don’t think the facts at all back up your contention that the word has now become broader use such that it has lost it’s tie to the original meaning, and my google search doesn’t back the claim you made about it.
Now, I’m not particularly bothered by her use, and certainly don’t think she was trying to say anything more than what she said. But it is clear that the term is primarily focused on accusations against Jews, and is tied to the murder of jews in Europe.
As such, I agree that it was a bad term to use. Palin’s message is a good one, and whether it should be or not, it is obscured by what everybody understands or WILL be led to understand about the term “blood libel”. That Giffords was Jewish will only make the use of the term worse.
Plus, in the end, part of being a good communicator is picking words that will enhance your message, not obscure it or take people off message. In that sense, the use of “blood libel” is demonstratably an error, because it HAS taken the discussion off what Palin was trying to say, and in a bad way.
And for that, you don’t have to agree with how others interpret “blood libel”, because it makes no difference — the results of the use of the word are clear, and it makes no difference whether that result is justified or not, because reaction simply “is”, and a good politician has to be able to predict reaction, and choose words that maximize the proper reaction.