I have heard many different pro-Israel arguments, and they basically fall into two categories. The first type are arguments usually used by those who view themselves as liberals or moderates on the Palestinian question:

*It is necessary for Israel to defend itself, even if, regrettably, that makes it necessary to temporarily curtail the civil liberties and lower the living standards of Palestinians;
*Jews need and deserve their own national state, for historical and security reasons;
*It is unfair to single out israel for criticism when many nearby states have worse human rights records in dealing with minorities;
*Israel has unique achievements to its credit, in the fields of science, medicine, agriculture and democracy, which put it out in front of the Middle East region, and maybe even make it globally competitive;
*Arab citizens of Israel enjoy greater freedom and a higher standard of living than they would elsewhere in the Middle East.

All well and good. Many on the left would be able to marshal counterarguments to all this, but these are essentially the best pro-Israel arguments, meaning that reasonable people of good will could disagree on them. However, not ONE of them is a justification for PERMANENTLY denying nationhood and self-determination to the Palestinians. Even the "security" argument will not work forever, since anyone who is sincerely interested in long-term security would try to come up with a way to reconcile security with civil liberties.
The second category of statements cuts right to the heart of the matter. Many pro-Israel people use the first category of positive, pro-Israel arguments and then jump straight to these without skipping a beat. They are the racist, anti-Palestinian arguments, which include the following:

*The Palestinians must pay the consequences for the bad acts of their leaders and radical groups that act in their name;
*The Palestinians do not value human life or civilization, and hence do not deserve their own state;
*In contrast to their Jewish neighbors, the Palestinians have not accomplished anything and have not tried to improve their own lives;
*The "Palestinians" are not a true people; they do not exist;
*Islam is an evil, bloody and oppressive religion which is a threat to Western freedom and progress.
*Israel has the right to keep territory it has conquered, and the Palestinians should go to an Arab country.

Racist arguments like these are a dead end. For one thing, most of these same slanders were used against European Jews a century ago. They can be employed against any oppressed group of people.
For another thing, most people in Western society in the 21st century know that it is racist to label and stigmatize an entire people based on the actions of some of their individual members. Most people know that political self-determination is a basic human right, that collective punishment is wrong, and that it is no longer the norm, in the 21st century, to recognize any right of military conquest. Most people know these things, except when the subject under discussion is Israel.
The Palestinians are not allowed to construct buildings, to dig wells, to develop their own economy or to travel where the economic opportunities are better. How much are they supposed to accomplish under these circumstances? And how improbable is it that many of them would choose despair and suicide?
Denying or re-defining the identity of the oppressed group is an old genocidal tactic. It has been used by Uncle Sam in denying recognition to Native nations, by the Belgrade government in denying that there are Bosnians, and by white supremacists in their insistence that today's Jews are descended from the Khazars and not from the Holy Land.
And as for the characteristics of Islam, show me one major religion that has not been evil, bloody or oppressive at one time or another. As Katha Pollitt wrote, "God changes everything."

I challenge any defender of Israel's treatment of the Palestinians to do so without resorting to the above racist arguments. In my opinion, it is impossible to defend such policies in any way that is consistent with the norms of human rights, democracy or international justice.
This applies to the Liberal Left as well. I believe it is inconsistent, and perhaps hypocritical, for an otherwise progressive person who opposes Bush and the Iraq War to express dismay at the appearance of Palestinian flags and pro-Palestinian slogans at a peace march. If all people are entitled to self-determination and nationhood, how could that not include the Palestinian people? And how could sympathy for such aspirations possibly be interpreted as anti-Semitism?
The only leftist who could legitimately oppose a nationalist movement of an oppressed people would be someone who opposes all nationalisms in general. Somehow, I don't think that describes a supporter of Israel.
Using the specter of anti-Semitism to excuse anti-Palestinian racism is a vile and contemptible tactic.

As a union member, I am appalled that the leadership of my own organization, United Teachers-Los Angeles, has caved to outside pressure and prohibited its own members from hosting a meeting (not "rally") of people who may endorse a boycott of Israel. If such meetings are to be prohibited, it should be a policy passed by our own House of Representatives. The ADL should not dictate its own policies to us.
We have hosted many meetings of groups which may seem controversial, including socialist groups, peace groups and groups opposed to military recruitment on campuses. Some may disagree with these goals, but all of these meetings have gone forward without our beloved union building being enveloped in flames and revolution. We have always practiced freedom of speech and association at UTLA -- until the subject was Israel.
This incident is truly chilling. It is an outrageous assault on free speech. It is an attack on academic freedom, reminiscent of the attacks on Edward Said at Columbia, with the difference that those attacks did not succeed, and this one did. It is also a direct challenge to our union's sovereignty and self-determination.
Hypocrites! Liberal hypocrites in the union hall and at City Hall! Hypocrites who pose as anti-racists while practicing the most pernicious forms of racism! If Israel and Palestine cannot be discussed in one of the most liberal cities in America, in one of the most progressive unions in the city, then when and where may it be discussed? Or perhaps that's what the ADL wants: that it never be discussed.
Incidentally, I do not think that there would be anything inherently immoral about boycotting Israel for its treatment of Palestinians. Such a boycott would be just as legitimate as boycotting America over the Iraq War. People may not like it or agree with it, but a boycott is a legitimate tactic that one uses to show disapproval of a nation's or a corporation's actions. The only question is whether such a boycott would be effective.

A supporter of Israel is not necessarily the same as an anti-Palestinian racist. There may be many people who are both, but the two are still distinct. Similarly, a supporter of Palestinian rights is not necessarily an anti-Semite or a terrorist. The two are distinct although many people are both.
To confuse these categories is to attack free speech and shut down any possibility of dialogue.