The controversy over the Bush administration's decision to allow a company from the United Arab Emirates to manage shipping operations at six major U.S. seaports has strained ties between the president and some of his strongest supporters, conservative Republicans.
The political firestorm over the ports controversy has been a bipartisan affair, with Republicans like New York Congressman Peter King breaking with the president over the issue.
"It has to do with a country that has had unusually close ties to terrorism and it is a risk we just cannot take," King said.
Opposition Democrats see a rare chance to criticize the Bush administration on national security, which in recent years has been the president's political strong point.
"If 9/11 was a failure of imagination, and Hurricane Katrina was a failure of initiative, this process is a failure of judgment," said Democratic Senator Hillary Clinton of New York.
Administration officials hope that the decision by the company to delay the ports takeover will give the president time to convince members of Congress that the changeover does not pose a threat to national security.
"This deal would not go forward, if we were concerned about the security for the United States of America," said Mr. Bush.
Political analysts say the president will have to make a special appeal to congressional Republicans to win their support on the ports deal. Republicans control both chambers of Congress, but are worried about losing seats in the November midterm elections.
Washington-based analyst Stuart Rothenberg says conservatives are quick to recall their successful effort last year to block Mr. Bush's nomination of Harriet Miers to the Supreme Court. The president withdrew her nomination after a barrage of criticism from many of his supporters, who argued that she was not sufficiently conservative.
"For some conservatives, it was like a cold dish towel across their face, reminding them that, 'wait a second, we thought we were totally supportive of this president, now we know, maybe we have to keep an eye on him.' And, conservative groups have become much more animated and activist and second guessing of the president," Rothenberg said.
The strains between the president and his Republican supporters in Congress could intensify in the months ahead, as lawmakers wrestle with a growing federal budget deficit, a major concern for many conservatives.