There was plenty of sulfur in the air at the United Nations on Wednesday, but it wasn't coming from George W. Bush. It was in the fire and brimstone of Venezuelan President Hugo Chávez.

Heads of state, including U.S. presidents, have sometimes used the U.N. General Assembly to lambaste other governments. But Chávez's diatribe was over the edge. It painted him as what he claims his U.S. counterpart is - dangerous, imperialist, and a threat to the world.

Lacking independent courts, a congress, or a healthy opposition to restrain him at home, Chávez is free to say whatever he likes. And he often does, using public platforms such the November 2005 Summit of the Americas to send U.S. free-trade proposals "to hell" and call Mexican President Vicente Fox Washington's "lapdog." He once reportedly described Pope John Paul II as a "potato" using a crude play on words after the pontiff met with him.

This time he said "the devil is in the house. He came here yesterday ... this place smells like sulfur," in reference to President Bush's participation in the General Assembly. Chávez alleged that "U.S. hegemonic pretensions put the survival of humanity at risk." He also called for changes in the world body to admit new member states from the developing world - such as Venezuela - as permanent members of the Security Council with veto power.

Chávez suggested that his government would become "the voice of the Third World" if his country were chosen to occupy a rotating seat on the Council. Member states will vote next month by secret ballot, with a choice between Guatemala and Venezuela. Venezuela has already served on the Council several times, while Guatemala, a U.N.-founding member, has yet to be selected.

Only a few weeks ago, Chávez was circling the globe lining up votes in developing nations like Belarus, Iran, Malaysia, and Syria. At the same time, he signed contracts in Russia worth $3 billion for two dozen Su-30 advanced fighter-bombers and more than 50 helicopters, and he agreed to buy some 100,000 Kalashnikov assault rifles and to have the Russians build him a munitions factory. In China and Malaysia he pledged to shift Venezuela's petroleum exports to South Asia.

Following the September meeting in Havana of the nations of the Non-Aligned Movement, Iran's President Mahmoud Ahmadinejad visited Venezuela to advance a growing petroleum partnership between Tehran and Caracas. In return for helping tap Venezuela's oil reserves, Ahmadinejad may expect collaboration in strengthening his own efforts against the United States, using the alliance of Venezuela, Cuba, and a burgeoning satellite state in Bolivia as platforms for intelligence gathering and arms trafficking in the Americas.

To close neighbors in the Western Hemisphere, Chávez's agenda is regional. Interviewed by Michael Shifter in the Washington Post last June, Peruvian President-elect Alan García said, "Chávez is using his millions of dollars to try and extend influence in the Andean countries, first Bolivia, now cloning a comandante in Peru [rival presidential candidate Ollanta Humala], then Ecuador, to surround Colombia, where he sees U.S. imperialism as strongest in Latin America."

But when he spoke at the U.N. General Assembly this week, President Chávez made it clear that his objective is to lead a global coalition to confront the United States. To do that, he must build an empire of his own. With improvised oil alliances, he seeks to turn a commodity into a strategic political tool. Through arms purchases, he hopes to shore up his own strength and supply neighboring guerrilla movements. In multilateral forums, he proposes to remake institutions to suit his purposes.

Over the long term, it's possible that the United States and other industrial democracies will reduce their reliance on foreign petroleum, and that then authoritarian rulers with oil won't have money to buy rebellion. For the time being, Venezuela's threat is limited - U.N. members will likely think twice before voting for Venezuela to occupy the rotating seat on the U.N. Security Council. Some may dislike America's prosperity and denounce its palpable influence in world affairs, but that doesn't mean they want to be identified with a capricious leader who seems to have become all he denounces.

Stephen Johnson is senior policy analyst for Latin America in the Davis Institute for International Studies at The Heritage Foundation.