What happened to that “adult conversation” the country was supposed to have about federal spending? If last week’s budget debate in and around the U.S. House of Representatives was an example of grown-up discussion, let’s hope we’re not soon subjected to a week of brats brawling in a sandbox.

Maybe President Obama was indulging in some wishful thinking when he suggested that Republicans and Democrats might embrace the concept of thoughtful dialogue — or maybe he was engaging in a bit of political posturing in hopes of casting himself as the only serious participant in the argument.

No matter. The budgetary bottom line remains in doubt, but the bottom line on the budget debate is painfully clear: Out with adult conversation, in with mindless sloganeering and brain-dead decision-making.

And we haven’t even started the debate over the president’s budget proposal for the 2011-2012 fiscal year. Last week’s bickering focused almost entirely on spending for the rest of the government’s current fiscal year, which ends in September.

Because Congress and Obama never agreed on a budget for 2010-2011, the federal government is operating under a temporary spending plan that expires March 4 — which means the government will run out of money if a new plan isn’t approved by then. Hence all the talk we’ve heard about a government shutdown.

The prospect of shutting down the government might seem appealing to many Americans, sad to say, given our frustration with its bloated inefficiency, but as a practical matter it’s a horrible idea. Like it or not, our massive federal government provides services that cannot and should not be interrupted.

And yet House Speaker John Boehner, R-Ohio, who sheds tears at the mere mention of the American dream, is evidently prepared to let America grind to a halt — denying services to its citizens and defaulting on its obligations at home and around the world — for no good reason other than to appease the tea party wing of the Republican Party.

Obama and his fellow Democrats are no better, of course, cynically attempting to position themselves above the fray with the intention of placing all the blame on Republicans when the government turns out the lights.

Senate Majority Leader Harry Reid of Nevada, for example, calls Boehner’s willingness to shut down the government “unacceptable” but hasn’t done a thing to raise the level of debate.

No one disagrees with Boehner and the GOP that annual budget deficits and the ever-increasing national debt threaten the nation’s economic stability. No one disagrees that government spending is out of control and needs to be restrained.

The problem is, Boehner and like-minded Republicans want to solve the problem by cutting government to the bone, virtually overnight, with no concern for the consequences, while Obama and the Democrats want to push the problem into the future by paying lip service to it now and letting someone else pay the bill later.

Adult conversation? Serious debate? How about a small dose of reality and a quick nod in the direction of common sense?

The nation’s debt-and-spending problem is urgent but it can’t be fixed overnight.

What’s needed is a long-term view, a thoughtful plan for digging out of the financial morass created by decades of shortsighted, self-serving leadership — or lack of leadership — in Washington, D.C.

The president appointed a commission to study the problem and the result was a serious set of recommendations for reforming entitlement programs such as Social Security and Medicare, overhauling the tax code to maximize revenue, and altering the profligate mindset that has dominated the budget process for too long. Neither the president nor the Congress wants any part of those proposals.

Republicans, meanwhile, have trapped themselves in the belief that they represent no one and no interest except the budget-bashing tea partiers who claim credit for giving the GOP its majority in the House of Representatives. And Democrats seem to believe their only constituents are clients of government services who will suffer from meaningful restraints on government spending.

No wonder we’re gridlocked.

Politicians in Washington and elsewhere spend a lot of time railing against “special interests,” and yet both major political parties are ignoring the pressing needs of the nation as a whole in favor of serving the interests of factions the politicians consider politically crucial. It’s a disgrace — and it’s a formula for disaster.