White House budget director Mick Mulvaney appeared in front of the House Budget Committee on Wednesday, and the stark differences in the way Democrats, congressional Republicans and the Trump administration view government spending became clear within the first 15 minutes.

In short: The Trump administration says huge cuts in government spending are critical to cut the deficit, and are a moral imperative. Mulvaney repeatedly came back to his argument that the government has a moral responsibility to spend taxpayer dollars wisely, arguing that government spending in many areas is ineffective and wasteful.

Democrats couldn't disagree more.

Freshman congresswoman Pramila Jayapal (D-Wash.), a legislator progressives see as a rising star, read a fiery opening statement in which she said the Trump budget is a “betrayal” and a “loss of hope and opportunities for millions of families.”

“The Trump budget is shockingly extreme, the antithesis of what the American people have said they want from their government,” Jayapal said. And therein lies the central divide between Democrats and Republicans about government spending.

The budget “represents a total disinvestment in our nation, and a complete departure from every standard of responsible governing,” Jayapal argued.

But the White House argues the opposite, saying spending is out of control, and the government has a responsibility to use tax dollars more responsibly — by spending fewer of them.

“What we did here is try to change the way Washington looks at spending,” Mulvaney said during his opening statement, laying out the Trump administration's basic view of the role of government.

“We no longer want to measure compassion by the number of programs that we have, or the number of people that are on those programs,” he said. “We want to measure compassion, true compassion, by the number of people we help to get off those programs.”

And Mulvaney isn't just making a moral argument; he's advocating for a total overhaul of the way the government spends money. Trump's budget proposal promises broad spending cuts across multiple executive branch departments, fitting in neatly with White House adviser Stephen K. Bannon's commitment to a “deconstruction of the administrative state.”

But does today's back-and-forth really matter? It's unclear that Mulvaney and the Trump administration have enough support from congressional Republicans to pass anything that looks remotely like their proposed budget. The Washington Post's congressional team reported yesterday that Senate Majority Whip John Cornyn (R-Tex.) is skeptical of Trump's proposed cuts, saying: “This is kind of the game. We know that the president’s budget won’t pass as proposed.”

Sen. Majority Leader Mitch McConnell agreed, saying Democrats will be involved in coming to an agreement that likely avoids many of Trump's proposed deep spending cuts in areas like medical research, housing, education and anti-poverty programs such as Medicaid. And polling indicates that such programs are overwhelmingly popular with American voters — a big reason for congressional Republicans not to agree with cuts.

While Mulvaney and the Trump administration are likely to see major changes to their budget proposal, today's hearing isn't entirely irrelevant. Members of Congress are beginning to draw battle lines around specific areas of the government they want funded. Today's hearing is just the launching point for a budget fight that could go on all summer.