What a different world we inhabit today versus, say, that of just a decade ago.

In days of yore, the U.S. was far and away the majordomo of the international business scene. But today we may be sliding, with China looking to catch up.

For instance, as you read this, Brazilian President Luiz Inacio Lula da Silva and Chinese President Hu Jintao have just hatched a $10 billion deal to provide Chinese funding to help Brazil's national oil company, Petrobras (NYSE:PBR), with exploration and production expenses.

The company plans to spend nearly $175 billion between now and 2014, eyeing the newly promising deep waters of the Santos Basin. In return for its financial help, China will receive 150,000 barrels a day of Brazilian crude the first year and 200,000 daily barrels thereafter until 2019. But both parties emphasized that the loan, which will carry a less than 6.5% interest rate, will be repaid in cash. The Chinese have already made similar direct loan arrangements with Russia and Kazakhstan.

At this point, Brazil's waters are full of international energy companies, including oilfield service providers such as Schlumberger (NYSE:SLB), independents like Anadarko Petroleum (NYSE:APC) and Devon Energy (NYSE:DVN), along with the Bobbsey Twins of deepwater drilling, Transocean (NYSE:RIG) and Diamond Offshore.

Brazil continues to need the technological expertise of these companies for the development of its complicated subsalt formations. And so, according to the parties involved in the new financial dealings, those companies' work will be unaffected.

In addition, Brazil's offshore operating scene is also the site of a successful partnership between ExxonMobil (NYSE:XOM) and Hess (NYSE:HES) -- and Petrobras. The work of these exploration and production companies will also remain unchanged by the new financial developments.

Why didn't Brazil come to the U.S. for funding? That very good question was probably best answered in an article earlier this week in The Wall Street Journal, wherein Petrobras CEO Sergio Gabrielli noted that "There isn't someone in the U.S. government that we can sit down with and have the kinds of discussions we're having with the Chinese."

With all this in mind, as in the past, I'd advise my Foolish friends to keep their eyes on Petrobras. It obviously has exciting things looming ahead. Beyond that, given the desirability of geographic diversity, I continue to view ExxonMobil as an awfully solid investment amid the current topsy-turvy energy markets.

 For related Foolishness:

Fool contributor David Lee Smith doesn't have financial interests in any of the companies named above. He does, however, welcome your questions and comments. Petroleo Brasileiro is a Motley Fool Income Investor recommendation. Try any of our Foolish newsletters today, free for 30 days. The Fool has a disclosure policy.