Bush Signs U.S.- Mexico Border Fence Bill President Bush signed into law Thursday a broad measure that calls for fencing a third of the 2,100- mile border between the United States and Mexico. "This bill will protect the American people, this will bill make our borders more secure. It is an important step in immigration reform," Bush said from the White House Roosevelt Room before putting pen to paper. Bush was joined by Vice President Dick Cheney, Senate Majority Leader Bill Frist, House Majority Leader John Boehner and several other lawmakers and administration officials.Bush said the United States is a nation of immigrants but also a nation of laws. "Unfortunately, the United States has not been in complete control of its borders for decades, and therefore, illegal immigration has been on the rise. We have a responsibility to address these challenges, we have a responsibility to enforce our laws, we have a responsibility to secure our borders. We take this responsibility seriously," Bush said. The Secure Fence Act of 2006 gives the secretary of Homeland Security 18 months to get "operational control over U.S. international land and maritime borders" by improving surveillance through personnel and technology as well as "physical infrastructure enhancements to prevent unlawful border entry and facilitate border access by U.S. Customs and Border Protection." The measure provides for at least two layers of reinforced fencing and the installation of additional barriers through 700 miles of portions of California, Texas andArizona. The legislation also demands the secretary report to appropriate committees in Congress on its progress and "the necessity, feasibility and economic impact" of the construction. It also gives the Department of Homeland Security the authority to decide where to use the fencing and where to use the department's preferred option of a virtual fence comprised of cameras, vehicles barriers, checkpoints, lighting and motion sensors, which officials say is more economical and just as effective. New Hampshire Republican Sen. Judd Gregg estimates that about half the 700 miles will actually be fence. The Congressional Budget Office estimates the project will cost roughly $2.2 billion, or about $3.2 million per mile. For complete election coverage, go to FOXNews.com's You Decide 2006 center The measure, sent to Bush on Tuesday by the Congress, is a compromise that gives Republican candidates in border states a winning campaign issue, with polls indicating strong support for tightening the border as an essential first step to getting control of illegal immigration. The act also represents a step in an ongoing process of political compromise between Republicans and Bush on the issue of how to deal with the estimated 11 million to 12 million illegal immigrants already in the United States.