Chuck Todd asked Trump about it on Meet the Press:
TODD: You know right now on Twitter, there is a trending retweet of yours. You tweeted someone from "ilduce2016" (okay, I wet myself, are you happy?), it was a Mussolini quote, but you didn't know it was Mussolini when you retweeted it, it said, "It is better to live one day as a lion than one hundred years as a sheep."* That's a famous Mussolini quote, you retweeted it, do you like the quote? Did you know it was Mussolini?
TRUMP: It's okay to know it's Mussolini. Yeah, look Mussolini was Mussolini. Its a very good quote, it's a very interesting quote, and I know it... I saw it... I saw what... I know who said it. But what difference does it make whether it's Mussolini or somebody else? It's certainly a very interesting quote.
TRUMP: That's probably why...
TRUMP: I, between Facebook and Twitter...
TODD: ...was a fascist.
TRUMP: ...have fourteen million people who...
TODD: ...do you want to be associated...
TRUMP: ...want to be able to vote. It's a very interesting quote and people can talk about it.
TODD: Do you want to be associated with a fascist?
TRUMP: No, I want to be associated with interesting quotes, and people, I have almost fourteen million people between Instagram and Facebook and Twitter, and all of that and we do interesting things. And I sent it out, and it certainly got your attention didn't it?
TODD: Well, it is trending on Twitter right now. Mister Trump, I have to leave it there. Stay safe on the trail. We'll see you Super Tuesday. It could be a big night for you.
I don't think Trump is either a particularly bright or particularly well-read man. But one thing he does know is that infallibility is the coin-of-the-realm in Trumpland. I have serious doubts that Trump recognized the quote, though the Twitter name of @ilduce2016 should have been a hint to someone on his staff if not to himself. (BTW, that Twitter account seems to be an epic trolling operation aimed specifically at Trump, note the Mussolini avatar they use is from his days as a newspaperman.) But just like the Sean Connery character Danny Dravot in the film, The Man Who Would Be King, his followers believe he is divine so long as he doesn't bleed. Once he starts bleeding he's just another pompous, privileged, rich guy -- like the other pompous, privileged, rich guys his most devoted followers believe have brought the nation to its knees -- and they will turn on him. If he admits error, the bleeding starts.
Of course, it matters where a quote comes from. Just because a quote is "interesting" doesn't give you license to throw it about, in effect endorsing it, if the author is Stalin, or Pol Pot, or Hitler, or a craven and inept Duce. But if Trump is interested in "interesting quotes", there are lots of interesting quotes out there if we want to ignore authors and context. For instance, "Work Will Make You Free" would be an epic slogan for welfare reform.
New polling shows .@realDonaldTrump absolutely killing it in beer halls all across Munich.
— Michael Krempasky (@krempasky) February 28, 2016
*in Appalachia, they say "better a live dog than a dead lion." I think we have a better record than the Italians.