Final answer:
President George W. Bush's administration attempted to overhaul U.S. immigration policy by introducing a guest worker program for illegal immigrants and expediting citizenship for Green Card holders in the military.
Step-by-step explanation:
During his presidency, George W. Bush sought changes to immigration policy with varying success. His administration was characterized by efforts to reform immigration laws, notably through a guest worker program that recognized illegal immigrants without providing a path to citizenship. In 2006, there was significant controversy when legislation was introduced by Congressman Jim Sensenbrenner to make illegal immigration a felony and to penalize those aiding immigrants; however, this punitive approach was met with massive protests.
Ultimately, under Bush's presidency, significant changes included the 2002 law simplifying and expediting citizenship for Green Card holders serving in the U.S. military, with approximately 70,000 soldiers benefiting over the following decade. However, deeper divisions and unresolved issues regarding the status of up to twelve million undocumented immigrants remained, as well as the construction of a fence along the U.S.-Mexico border.