President Donald Trump has unveiled a 1.15 trillion dollar budget, a far-reaching overhaul of federal government spending that slashes many domestic programmes to finance a significant increase in the military and make a down payment on a US-Mexico border wall.
Mr Trump's proposal seeks to upend Washington with cuts to long-promised campaign targets such as foreign aid and the Environmental Protection Agency as well as strong congressional favourites such as medical research, help for homeless veterans and community development grants.
"A budget that puts America first must make the safety of our people its number one priority - because without safety, there can be no prosperity," Mr Trump said in a message accompanying his proposed budget that was titled America First: A Budget Blueprint to Make America Great Again.
The 54 billion dollar (£43 billion) boost for the military is the largest since President Ronald Reagan's Pentagon build-up in the 1980s, promising immediate money for troop readiness, the fight against Islamic State militants and procurement of new ships, fighter jets and other weapons.
The 10% Pentagon boost is financed by 54 billion dollars in cuts to foreign aid and domestic agencies that had been protected by former president Barack Obama.
The budget goes after the frequent targets of the party's staunchest conservatives, eliminating the National Endowment for the Arts, legal aid for the poor, low-income heating assistance and the AmeriCorps national service programme established by former president Bill Clinton.
Such programmes were the focus of lengthy battles dating to the Republican takeover of Congress in 1995 and have survived prior attempts to eliminate them.
Politicians will have the final say on Mr Trump's proposal in the arduous budget process, and many of the cuts will be deemed dead on arrival.
White House budget director Mick Mulvaney acknowledged to reporters that passing the cuts could be an uphill struggle and said the administration would negotiate over replacement cuts.
Mr Mulvaney also went after Republican favourites, including aid to rural schools and health research, while eliminating subsidies for rural air service and the federal flood insurance programme that is a linchpin for the property market, especially in coastal southern states and the north east.
Mr Trump's Republican allies on Capitol Hill gave it only grudging praise, if any.
"Congress has the power of the purse," reminded House Appropriations Committee chairman Rodney Frelinghuysen.
"I look forward to reviewing this," said House Speaker Paul Ryan.
"This is not a take-it-or-leave-it budget," Mr Mulvaney admitted.
Law enforcement agencies such as the FBI would be spared, while the border wall would receive an immediate 1.4 billion dollar (£1.1 billion) infusion in the ongoing fiscal year, with another 2.6 billion dollars (£2.1 billion) planned for the 2018 budget year starting on October 1.
Mr Trump repeatedly claimed during the campaign that Mexico would pay for the wall when, in fact, US taxpayers will foot the bill.
Twelve of the government's 15 cabinet agencies would absorb cuts under the president's proposal.
The biggest losers are agriculture, labour, state and the cabinet-level EPA.
The defence department, department of homeland security and department of veterans' affairs are the winners.
More than 3,000 EPA workers would lose their jobs and programmes such as Mr Obama's Clean Power Plan, which would tighten regulations on emissions from power plants seen as contributing to global warming, would be eliminated.
Popular EPA grants for state and local drinking and wastewater projects would be preserved, however, even as research into climate change would be eliminated.
Mr Trump's proposal covers only roughly a quarter of the approximately four trillion dollar federal budget, the discretionary portion that Congress passes each year.
I t does not address taxes, Social Security, Medicare and Medicaid, or make predictions about deficits and the economy.
Those big picture details are due in mid-May and are sure to show large - probably permanent - budget deficits.
Mr Trump has vowed not to cut Social Security and Medicare and is dead set against raising taxes.
"The president's going to keep his promises" to leave Social Security and Medicare alone, Mr Mulvaney said.
But the budget increases user fees, boosting the airline ticket tax by one dollar per one-way trip.
The so-called "skinny budget" is indeed skimpy, glossing over cuts to many sensitive programmes such as community health centres, national parks, offering only a vague, two-page summary of most agencies, including the Pentagon, where allocating its additional billions is still a work in progress.
Mr Trump's proposal is sure to land with a thud on Capitol Hill, and not just with opposition Democrats outraged over cuts to pet programmes such as renewable energy, climate change research and rehabilitation of housing projects.
Republicans such as Senator Rob Portman of Ohio are irate over planned elimination of a programme to restore the Great Lakes.
Top Republicans such as Majority Leader Mitch McConnell of Kentucky and Senate Foreign Relations Committee chairman Bob Corker of Tennessee are opposed to drastic cuts to foreign aid.
And even defence hawks such as Armed Services Committee chairman Mac Thornberry of Texas are not satisfied with the 54 billion dollar increase for the military.
Before the two sides go to war over Mr Trump's 2018 plan, they need to clean up more than 1.1 trillion dollars in unfinished agency budgets for the current year.
A temporary catch-all spending bill expires on April 28; negotiations have barely started and could get hung up over Mr Trump's request for the wall and additional border patrol and immigration enforcement agents, just for starters.
Some of the most politically sensitive domestic programmes would be spared, including food aid for pregnant women and their children, housing vouchers for the poor, aid for special education and school districts for the poor, and federal aid to historically black colleges and universities.
But the National Institutes of Health would absorb a 5.8 billion dollar (£4.7 billion) cut despite Mr Trump's talk in a recent address to Congress of finding "cures to the illnesses that have always plagued us".
Subsidies for airlines serving rural airports in Trump strongholds would be eliminated.
It would also shut down Amtrak's money-losing long-distance routes and kill off a popular 500 million dollar (£404 million) per year programme for highway projects created by Mr Obama.