Iranian President Mahmoud Ahmadinejad was embarrassed at a recent U.N. conference in Rio de Janeiro by perceived snubs by leaders of host country Brazil and other nations.

Iran’s blowhard president, who has trumpeted his own role in fostering closer Iranian ties to Latin America, found himself relegated to the sidelines at last week’s U.N. Rio +20 summit, as many leaders shunned meetings with him.

For some Latin American hospitality, Ahmadinejad had to travel to Bolivia and Venezuela, where anti-American, populist authoritarian leaders once more schemed, sang dirges for the impending “demise of imperialism” (read the U.S.), and promised to continue a way forward for “justice-seeking nations.”

Iran was also shut out of U.N.-sponsored talks slated for Saturday on Syria, where it has played an unhelpful role by propping up the Syrian dictatorship, its most important Arab ally. As The Heritage Foundation’s Kim Holmes noted, Iran has been a big part of the problem in Syria and does not deserve to be treated as a potential part of the solution.

Perhaps one reason that Iran finds itself increasingly isolated, beyond its long-standing support for terrorism and nuclear defiance, is that its officials continue to harangue their diplomatic interlocutors with anti-Semitic diatribes and far-fetched conspiracy theories. Britain, which has sought to find common ground with Iran on combating drug smuggling, denounced the ignorant and bigoted statements of Iran’s vice president, Mohammad Reza Rahimi, who blamed the Jewish religion and Zionists for international drug smuggling at another U.N. conference in Tehran last week.

Such statements are a blot on the reputation of the U.N., which never should have convened a conference in Iran in the first place. But Rahimi’s loony hate speech is also typical of Iran’s Islamist extremism and its hostile approach to the outside world, which have contributed to its growing international isolation.