Petrobras CEO José Sergio Gabrielli was flush with bullish insights when he stopped by the Journal's New York office last week to talk about the Brazilian oil company.

One reason for Mr. Gabrielli's optimism is last year's discovery of the offshore Tupi field, which is said to contain between five billion and eight billion barrels of black gold. Another, equally important reason is that, according to Mr. Gabrielli, neither environmentalists nor Brazilian politicians have raised concerns about exploiting oil in the waters off the Brazilian coast.

That's quite a contrast with attitudes in the U.S., where offshore exploration and development has been all but shut down save in the Gulf of Mexico. One company official explains the difference by saying that Brazilians understand the importance of energy to their future, while Americans do not.

I have another theory. And mine fits the pattern of resource development – or lack thereof – all over the Western Hemisphere. It comes down to this: Where government has the property right, restrictions on development tend to be low. But when the private sector is the owner, environmental concerns blossom.

Exhibit A is Petrobras. Not only did Mr. Gabrielli say there is no appetite for stopping offshore projects in his country. He went further. "Brazil has one of the freest and most investor-oriented regulation in the world. Even freer than the United States of America," he said, referring to the climate for oil exploration.