This week top Treasury Department officials addressed concerns both foreign and domestic over how open the U.S. remains toward investment from overseas, attempting to assuage those worried that the government seeks to restrict the activities of sovereign wealth funds and urging measures to counter what they described as a growing move towards protectionism.

Speaking in Pittsburgh today at an event on global trade, Undersecretary David McCormick spoke to the security anxieties many U.S. citizens feel toward foreign investments. His remarks came just one day after Treasury Secretary Henry Paulson used a speaking engagement before the U.S.-United Arab Emirates Business Council in Abu Dhabi to address concerns abroad over just how welcome the U.S. has become to foreign investment.

Many Americans are "fearful about the implications of foreign investment," McCormick acknowledged in his speech to the World Affairs Council. "In the wake of September 11th, concerns about national security have led Congress and the public to take a careful look at investment from outside our borders." He went on to cite the political outcry over a 2006 deal that would have allowed a Dubai-based company to manage six major U.S. ports, as well as frequently negative publicity surrounding investment from sovereign wealth funds.

"I have met with many leaders from the Middle East who ask if the United States really continues to welcome foreign investment," said Paulson. "Some here worry about growing protectionist sentiment in the United States, and they also worry specifically that U.S. sentiment toward Middle East investment has been permanently affected by the Dubai Ports World case."

But McCormick and Paulson stressed that such concerns would not steer the country away from its goals of opening markets and expanding trade. "America will keep our markets open at home to investment from private firms and from sovereign wealth funds," Paulson said. "We reject measures that would isolate us from the world economy."

There has been increasing anxiety on Capitol Hill in recent months about the rapid growth of sovereign wealth funds. But rather than trying to limit the activities of these funds, Paulson said, the U.S. supports the International Monetary Fund's quest to establish guidelines for countries regarding such investment. "We are trying to quell calls for restrictions by urging sovereign wealth funds to endorse best practices" in order to allay concerns about transparency and security, said Paulson.

"As the United States has reformed our investment review regime, we have been careful to not reach beyond national security to broader industrial or economic interests," said Paulson.

He added that, “In the two years following DP World, the number of U.S. acquisitions by Gulf country investors rose by more than 100 percent, and the combined value of those deals rose by more than 400 percent. Despite what the headlines may say, our investment review process has looked at just over 10 percent of the publicly announced acquisitions by Gulf investors, and all of those transactions were allowed to proceed."