For those who had thought the presidential campaign was too small for two divorced mayors of New York who favor gay rights and abortion rights, things certainly are taking an interesting turn. Just as Mayor Bloomberg was in China offering an optimistic vision of the benefits immigrants bring to America, Mayor Giuliani was releasing a television commercial boasting of how he was going to keep immigrants out of America. What a contrast.

“New York City has so many Chinese restaurants because we are home to more people with roots in China than any other city outside of Asia — and because these New Yorkers are the living embodiment of the American dream,” quoth Mr. Bloomberg. He noted that New York City has more than 2,500 Chinese restaurants. “Chinese immigrants bring with them a tremendous work ethic and a great respect for education, and they also bring an incredible spirit of entrepreneurship, opening not only restaurants, but businesses of every kind. I admire entrepreneurs. I know how hard it is to take such a big personal risk.”

Said Mr. Bloomberg, “America became the world’s leading economic nation by welcoming immigrants — and New York became America’s leading commercial city by inviting them to stay. …Consider this: Half of the Americans who won Nobel prizes in physics in the past seven years were born abroad; More than half the people with PhDs working in America are immigrants; Revolutionary technology companies like Sun Microsystems, Yahoo, and Google were all founded or co-founded by immigrants. In fact, a quarter of all Silicon Valley companies were started by entrepreneurs from two just countries: China and India.…Right now, our immigration laws are preventing too many of tomorrow’s entrepreneurs from working in America.”

Mr. Giuliani’s campaign commercial, which the campaign said is airing in New Hampshire and Boston, took the opposite approach. It says, “People are frustrated over immigration because the government has been talking about solving this for twenty or twenty-five years, and it’s just gotten worse. What we need here is leadership. Build a fence. Train the border patrol. Have a BorderStat system. Have a tamperproof ID card. And then if you become a citizen you have to be able to read English, write English, speak English and understand American civics. We can end illegal immigration. The technology exists to do it, the people exist to do it. Now we need the political leadership and will to get it done. I’m Rudy Giuliani and I approve this message.”

It is our belief that Mr. Giuliani can – not to put to fine a point on it – lose his campaign on this issue. The only positive note about immigrants in the Giuliani commercial was a brief visual at the end showing what appears to be a citizenship swearing in-ceremony. Most of the other visuals in the ad are of anti-immigration protesters. If Mr. Giuliani thinks he can air these sorts of ads in New Hampshire and not pay the price in the immigrant-rich states he is hoping to win, like Florida, New York, and California, he is deluding himself. The sad thing is that he has been maneuvered into it by Governor Romney, who has been attacking Mr. Giuliani for running New York as a “sanctuary city.” Mr. Giuliani spoke in this week’s debate of the need for candidates to offer an optimistic, growth-oriented message. Why isn’t he following his own advice?

In the meantime, the Wall Street Journal was yesterday running an unscientific online poll of its readers on whether Mr. Bloomberg should get into the presidential race. Early yesterday evening, with more than 2,000 votes cast, sentiment was running two to one in favor of Mr. Bloomberg, with 35% of respondents saying they would definitely vote for him and 26% saying they might vote for him. If he does run, immigration will be an issue on which he can find differentiation and make a valuable contribution to the national debate.