This week's column is an open letter to New York City Mayor Michael Bloomberg.

Dear Mayor Bloomberg,

Last week, in the presence of Dutch dignitaries visiting New York City to mark the 400th anniversary of Henry Hudson's remarkable first voyage on behalf of the Dutch East India Co. to "Nieu Amsterdam" (New York), you spoke of the need to safeguard freedom of expression. "Of course, I do not appreciate everything I hear," you said, according to a translated report from the Amsterdam newspaper De Telegraaf. "But when you start restricting that, you step on a slippery slope. Before you know it, you can no longer say what you want."

Congratulations, Mr. Mayor. With those words, you have became the first and only public official in the United States to express support, at least in principal, for Dutch parliamentarian Geert Wilders, leader of the Dutch Freedom Party (PVV). Wilders, at the unexpected order of a Dutch appeals court, now faces criminal prosecution for exercising his freedom of expression about Islam. As the headline over your remarks in Amsterdam's De Telegraaf puts it, "Bloomberg helps Rutte and Wilders" -- Rutte being Mark Rutte, a second Dutch parliamentarian (and, in fact, Wilders opponent) who has come out against Wilders' prosecution.

This is either big stuff, Mr. Mayor, or I am grasping at straws. Maybe both. The fact is, an unnaturally incurious and stony international silence has met the outrageous Dutch decision to bring a duly-elected leader before a tribunal of judges for what he has said, written and expressed about Islam -- for committing, according to postmodern parlance, "hate speech."

Such a term is postmodern, but the crime it describes is premodern, a violation, in non-Western eyes, of the medieval Islamic prohibition against any and all criticism of Islam. Thus, this trial of the 21st century will turn on the will of an advanced, secular Western state to force one of its citizens to accept a fossilized, sectarian, non-Western taboo. That this citizen is Holland's leading proponent of advanced, secular and Western liberties, starting with freedom of speech, adds a circular irony to the state's shameful action. And no one, save a handful of mainly anti-jihad writers, seems to care.

That is, not only public officials but also media are ignoring this story about the erosion of freedom of speech in the West. And that goes for America's talk radio and cable kings, some of whom are headquartered in New York City. From Rush Limbaugh to Sean Hannity to Mark Levin: Even as these men, among other broadcasters, alternately bristle and rail at the likelihood that they themselves may be targeted by First Amendment-flouting "hate-speech" controls in our brave, new Obama world, they fail not only to uphold Wilders' right to free speech, they fail to notice the threat to it.

All of which is why your statement, Mr. Mayor, in front of your Dutch visitors about the slippery slope of speech restrictions -- "Before you know it, you can no longer say what you want" -- sounded like a declaration of independence from the Sharia-serving speech codes that the West increasingly adopts to regulate expression and debate.

And that includes New York. As you may know, over at the United Nations in December, the United States (and the Netherlands, for that matter) voted against a resolution introduced on behalf of the Organization of the Islamic Conference (OIC) to promote a Sharia-serving speech code. Then again, you may not know. There were no news stories in the local press -- Times, Post or Daily News. Is this more evidence of the pattern of Western silence on Sharia-serving speech codes generally? Hard to say.

Anyway, the resolution, which prohibits the "defamation" of religion, passed 86 to 53 with 42 abstentions. A dangerous gag on speech even in ecumenical theory, the resolution mentions only Islam, and the "defamation" it describes includes any linkage between Islam and terrorism.

It was left to the Israeli ambassador to the United Nations to point out that the resolution objects to efforts "pursued by extremist organizations and groups aimed ... at incitement to religious hatred," but omits any mention, for example, of what he called "the toxic religious incitement and indoctrination of Palestinian children, and the brutal persecution of Christians in Gaza," adding: "Where is the rejection of the Hamas Covenant which states: `No war takes place anywhere in the world without the Jews behind the scenes having a hand in it. ... Whenever they fan the flames of war, Allah will extinguish them.'"

Such rejection is nowhere. It is not "defamation of religion" the U.N. resolution prohibits, it is defamation -- read: criticism -- of Islam. As such, the resolution is an instrument of Sharia. But hardly anyone takes note.

Certainly, the General Assembly of the United Nations doesn't represent New York City. Still, I would like to draw your attention to a recent incident that took place last month as you dined inside the Marriott Marquis hotel on Broadway, a guest at the annual American Israel Public Affairs Committee dinner.

You may know from a brief New York Post account that 10 "pro-Gaza" demonstrators were arrested for chaining themselves to the hotel. What you probably don't know is that a New York Post photographer was prevented from taking pictures of the demonstration by "pro-Gaza" protestors. Mr. Mayor, you should watch the video (by the blogger VigilantSquirrelBrigade) of the photographer being harassed and, at one point, bashed over the head with placards by the demonstrators. (To find the video, Google: "Pro Gaza Rally Assaults Photographer.") Worse, you should watch the photographer's treatment at the hands of apathetic, unresponsive New York City police who ignored his plight. In failing to act, in looking the other way (literally), the NYPD not only ceded control of Broadway to the mob, it also failed, miserably, to protect freedom of speech in New York.

A small thing? Clearly, this is a blip next to the Dutch case against Wilders' freedom of speech, or the U.N. vote against freedom of speech. But it is highly significant nonetheless, and something you, as mayor, should know about so you can ensure freedom is better protected on your streets. A little intimidation here, a little restriction there, and there's your slippery slope. All of which is to say, Mr. Mayor, it's one thing to declare that the slippery slope exists; it's another to figure out what to do when we are already on one.