Matt Duss digs into the factual basis for the allegation, repeated by Andy McCarthy and Jennifer Rubin, that Palestinian crowds were celebrating the murder of Israeli settlers by passing out candy and finds...nothing:
So it seems that what happened here is that a pro-Hamas website tried, lamely and offensively, to spin the Itamar murders as a bold, praise-worthy act of resistance. An Israeli tabloid then reported this (now disappeared) item in typically steroidal fashion. Conservative bloggers then swarmed on it. And that's how a non-existent mass demonstration of anti-Israel hatred ended up under the Washington Post’s banner as an actual fact, probably to be repeated in op-eds and AIPAC fundraising letters for years and years to come.
McCarthy's spin was particularly ugly, using the incident to justify Rep. Peter King's useless MUAC hearings. Even if the story were true, to McCarthy there's no actual difference between Muslims in Gaza and Muslims in Detroit. They're all just mindless drones acting in service to McCarthy's "Grand Jihad."