Bush, who inherited a $236 billion surplus and a declining economy when he took office in 2001, hopes to put the government on a path to a $207 billion deficit by fiscal 2010. The government expects to end the current fiscal year $427 billion in the red.
That's a record in dollar terms, but not as a percentage of the economy, which is considered a more important gauge of the government's financial health.
The budget would accelerate the shift in federal priorities that began with the terrorist attacks on Sept. 11, 2001. Four years later, the threat of terrorism has become a fact of life that influences federal spending across the board.
Bush's plan to increase defense spending by about 5 percent next year would bring the total increase since 2001 to 41 percent.
The $419.3 billion defense budget for 2006 would consume about half the money that Congress has available for programs covered by the annual budget process.
Funding for homeland security, which already has tripled since 2001, would increase by 8 percent next year, to nearly $50 billion.
About $34.2 billion would go to the Homeland Security Department, but more than two dozen other agencies also have responsibility for homeland-security programs.
The fear of a chemical, biological or nuclear attack is a recurring theme in the president's budget.
The FBI would get $5.7 billion -- an 11 percent increase -- to help pay for more translators, intelligence analysts and overseas agents.
Despite a 6 percent cut in overall spending at the Environmental Protection Agency, the agency would get a 73 percent increase -- to $185 million -- for programs related to homeland security.
The EPA is responsible for decontaminating any sites that are hit by weapons of mass destruction.
In addition, interest on the federal debt would take a $211 billion bite out of the budget, more than twice the combined amount allocated for the EPA, the Energy Department, federal law enforcement and foreign aid.
Bush offered no new details on his plans for overhauling Social Security, but said he hoped to save $45 billion during the next 10 years in Medicaid, a federal-state health care program for the poor.
Even with the changes the president advocates, Medicaid spending would increase by about 7.2 percent a year.
The proposed savings would put new burdens on state governments while many of them are struggling to avoid deficit spending.
The National Governors Association said Bush's plan could force cuts in Medicaid services to the elderly and people with disabilities, which receive the biggest share of Medicaid spending.
"The Medicaid program is growing rapidly because health care inflation is running two to three times the general inflation rate and the case load has grown 33 percent over the last four years," the association said in a statement responding to the president's budget.
"Governors have little control over these two cost drivers, and do not want to be in the position of having to choose between funding health-care programs for grandparents or programs for their grandchildren."