Turkey has cancelled a NATO air force exercise, because of pressure from pro-Palestinian media and political groups to not allow Israeli aircraft to participate (as they had always done). The immediate cause of that was the Israeli military operation in Gaza earlier this year, to stop the Palestinian rocket attacks on Israel. The operation was a success, but leftist and Islamic groups successfully portrayed Israel as the aggressor and war criminal. Arabs, and especially the Palestinians, have been waging a propaganda campaign for decades, demanding that Israel be destroyed, and all Jews be driven out of the Middle East. Many in the West, especially leftist groups, have bought into the Arab propaganda.
The Arabs have successfully delivered a more rational and reasonable argument to non-Arab speaking audiences. But their Arab language propaganda has been very anti-Semitic and pro-genocide. While the non-Arab message is one of negotiation and peacemaking, the Arab language message is all about killing Jews and destroying Israel.
There is also a lot of outright lying used. For example, Palestinians claimed that the 22 Day War last January "indiscriminately killed civilians." Hamas claimed that 1,434 Palestinians were killed. Hamas further claimed that only 235 were Hamas fighters, while another 239 were police officers, and 960 of the dead were civilians. Hamas admitted that most of the "civilians" were men, mostly of military age. They also claim that 121 of the dead civilians were women and 288 were children (defined as anyone under 18).
Israel scrutinized all reports of Palestinian deaths during the 22 day war. Israel has a lot of data on who Gazans are, both from when they ran the place (until they withdrew in 2005) and from intel collected since then. This included data that appears on websites, where Hamas, and other Palestinian terrorist groups, tend to memorialize their dead. This is important for morale, and helps with recruiting, but it has also proved to be an embarrassing, if inadvertent, admission that Hamas has lied about who died.
Israel found that over two-thirds of the Palestinian dead were men of military age (18-35). They also found that most of the "children" were teenage males, and some have been found memorialized in Palestinian web sites as "martyred fighters." That means they were armed and on the payroll. Moreover, Hamas openly uses younger kids as lookouts and messengers. Lots of these "fighters" got killed simply because they deliberately placed themselves in the combat zone, or were sent there by their adult commanders. Thus over 70 percent of the Palestinian dead were working for Hamas, and most of them were armed.
This tracked with reports from Israeli troops about the number of Hamas fighters they had encountered, and killed. Hamas had claimed that only a third of the dead were men of military age. This does not square with what Palestinian newspapers and websites published. Thus Hamas was trying to pass off its military dead as "innocent civilians," and assuming that no outsiders would bother to read the Palestinian Arab language web sites and media.
Gaza is not the first time this kind of scam has been attempted. Take the 2002 battle in Jenin, in the West Bank. Jenin was a refugee camp that had been taken over by five terrorist groups (including Hamas) and used as a base for launching over a hundred attacks on Israeli civilians. Israel finally came in to clear out the terrorists. The fighting went on for nine days, and even before it was over (with a crushing defeat for the terrorists) it was being claimed that the Israelis had massacred over a thousand Arab civilians. But once a detailed investigation was conducted, outside experts (most of them pro-Arab) concluded that only 53 Arabs were killed (only five could be conclusively proven to be civilians), along with 23 Israelis (who went to extraordinary lengths to avoid civilian casualties). The rest were armed Palestinians trying to kill Israelis. Some 200 Arab terrorists also surrendered, and a few escaped the camp.
The Arab "hate Israel and Jews" campaign was not popular in Turkey until Islamic radicals began to push back at decades of secularism, and promote Islamic conservatism as a cure for the corruption that has hobbled Turkey for centuries. The current Turkish government is dominated by Islamic political parties. Many Turks are not so sure that Islamic conservatism is a cure for anything, but a significant minority does, a large enough minority to damage generations of good will with Israel.