This started out as a response to a poster that used the term "Zionist" (without any modifier) to vilify Hillary Clinton. This is something that I myself have mistakenly done before to define those that defend the Israeli state in spite of its abuses of the Palestinian people.
This is the anniversary of the so called "Operation Cast Lead". In it Israeli military attacks on Gaza killed ~1400 and wounded maybe 5000, the majority of whom were women and children. They also destroyed billions of dollars worth of infrastructure that with Israel and Egypt's blockade is difficult to rebuild. They terrorized the whole population of 1.5 million, and many of us would call this a "terrorist" attack. The details of this attack included some particularly horrendous details, including burning children to death with white phosphorus and targeting a UN school where people were led to believe they could find a safe haven in a reign of terror. Ambulances and hospitals were also intentionally targeted. Though some of the corporate media framed it as a "war" only 13 Israelis were killed and of these at least 4 were known to have been victims of Israeli "friendly fire". This was no "war". This MSNBC report from that time documents some of the horrors:
Many of us, both Jewish and non-Jew, understandably, now want to speak out against this and other injustices perpetrated by the Israeli government over the last 60+ years. 85 year-old holocaust survivor Hedy Epstein, who went on a hunger strike to pressure Egypt to allow her Gaza Freedom March, with 1300 members from over 40 countries into Gaza, has recently been most prominent among us Jews speaking out against what we believe has been horrendous Israeli government policy. In looking for words to define those that defend the abusive and violent behavior of the Israeli government towards the Palestinians, many seize the unmodified term "Zionist" to define this group. While better than those that just lump as "Jews" all who defend this behavior, "Zionist" still lumps in many who do not actually support this Israeli government behavior. We must always remember to divide and conquer the opposition. That means we are foolish to alienate potential allies that we have lumped into an overly simplistically defined opposition. The essence of prejudice is lumping together people who may not fit your negative stereotype of a whole group.
You alienate some possible allies when you vilify them with the unmodified term "Zionist". Many of my fellow Jews grew up with this happy image of a Jewish homeland in Israel with no thought and usually relatively little or no knowledge of the terrorism that the Jewish terrorist group Irgun (including Rahm Emanual's dad Benjamin) perpetrated in the 30's and 40's. (The acts of this group have even been defined by the New York Times as "terrorist". See Wikipedia's article on Irgun.) Most of my fellow progressive Jews have little or no knowledge of the horror stories of how sufficient Muslims were violently evicted from their land or killed in 1948, in order to create a Jewish majority state. There may also a tendency to dismiss these stories as false, exaggerated or out of context if they do hear them.
This is not all their fault. Most of our media has been dominated by an element that defends anything the state of Israel does and almost all of the information we have gotten has been twisted through this filter. Virtually every attack upon a Palestinian has been framed in this media as "defensive" or as a "counter-attack", while virtually every attack by a Palestinian upon Israelis has been framed as "terrorism". It doesn't matter that of the violence done to each group by the other, the vast majority of the victims were Palestinians and the perpetrators were Jewish Israelis. This includes the killings, the injuries, the property destruction and confiscation and the abuses of one group upon the other in general. Though many of my fellow Jews like to think of themselves as "victims'" I don't know any Jew that would ever want to change places with the Palestinians in Gaza or the West Bank or anywhere else for that matter.