When is a budget not a budget? When it’s not so much about dollars and cents as about politics and public perception. When the person who conjured up the numbers for the budget says it’s not really about the numbers.

That person would be U.S. Rep. Paul Ryan, R-Wis., chairman of the House Budget Committee, who last week unveiled his committee’s proposed federal budget for 2012.

“This is not a budget,” Ryan said. “This is a cause.”

And so it is. The Ryan budget, which at least one pundit dubbed a “manifesto,” reduces to cold numbers the feverishly impassioned attacks on government spending and debt that defined last fall’s congressional elections. Ryan and his colleagues captured a majority of seats in the House of Representatives, many of them with crucial support at the polls from the anti-deficit brigades of the tea party movement. House Republicans promised tea party voters they would wage war on deficit spending; this budget lays down the rules of engagement for that conflict.

Ryan’s budget allows for a breathtaking amount of spending — $3.53 trillion. But that’s $179 billion less than President Obama wants to spend in his 2012 budget proposal. And Ryan’s plan would cut the operating deficit to $995 billion next year, a noticeable improvement from the $1 trillion-plus deficits of recent years.

If the budget cuts and savings envisioned by Ryan are enacted — along with his proposal to reduce income tax rates to promote economic growth — the deficit could shrink to $385 billion by 2021.

But, as we said — as Ryan said — this budget is about much more than the numbers.

ENTITLEMENT REFORM

To reach his fiscal goals, Ryan is proposing a massive overhaul of two entitlement programs that symbolize the nation’s long-standing commitment to providing health care and social services for the elderly and underprivileged: Medicare and Medicaid.

Medicare, the senior citizens’ health care program, would be restructured from a system of universal health insurance paid for by the government, to a voluntary insurance program with the government providing subsidies in the form of “premium support” paid to insurers.

And Medicaid — in Maine, it’s called MaineCare — would no longer exist as a federal program overseeing health care for the needy and subsidizing nursing home care for the elderly; instead, states would receive lump sums of money known as “block grants” and determine for themselves what services would be provided.

Not surprisingly, given the exalted status of Medicare and Medicaid as key elements of the social “safety net” in America, the proposed changes to these programs have commanded far more attention from the news media than the cuts to other programs and services proposed by Ryan — and generated far more opposition from Democrats and assorted social progressives who believe that government’s primary responsibility is to help those in need.

And that might be exactly what Ryan had in mind. If all the wrath from opponents of the budget is focused on the proposed dismantling of Medicare and Medicaid, then little outrage is left for the very substantial reductions Ryan is seeking elsewhere in the budget.

A CALL TO ARMS

Ryan and his Republican colleagues must be aware that the Democrat-controlled Senate will never enact and the Democratic president will never sign a budget that slashes Medicare and Medicaid so dramatically. So those cuts could easily end up being negotiated away in exchange for major cuts to other programs.

But that’s the budget part. The cold numbers on the ledger sheets. And Ryan’s budget, let’s remember, is not a budget. If it becomes law in any form, Ryan’s budget will bear little resemblance to the specific plan he presented last week. The budget that isn’t a budget is really a call to arms — a cause, as Ryan said — that establishes the framework for a serious debate about the future of the country. It will be the rallying cry in the 2012 elections for Republicans demanding balanced budgets and debt reduction — and for Democrats, including the president, who will accuse their Republican opponents of trying to balance the budget on the backs of the elderly and the needy.

Many voters, and many Republicans in Congress, clearly believe that argument was settled in the 2010 elections; but it wasn’t, because it’s one thing to talk about spending cuts in vague, generalized terms and quite another to seriously discuss the drastic measures that will be needed to actually balance the budget.

So whatever anyone says about Paul Ryan’s budget as a budget, those critiques are largely beside the point. As a cause, as a call to arms, as a rallying cry — as a framework for debating the nation’s future, the Ryan budget is exactly what this country needs at exactly the time we need it.