In his 2000 budget, the one with the famous ”$100-billion tax cut” (it wasn’t anything of the kind, but let that pass), Paul Martin pledged to hold increases in program spending to no more than “inflation plus population growth”—about 3% per year. At the time, he presented this as only sensible. “Let there be no doubt,” he declaimed. “We will control spending.”

As it turned out, they didn’t: Over the past four years, spending has grown by more than 30%, or roughly 7% per annum. And suddenly, 3% spending growth is no longer sensible: It’s a biblical calamity. When you hear the Liberals attack the Conservative fiscal plan as one that would make Canada, in Ralph Goodale’s words, a “colder, harsher” place (what, the Tories are going to change the weather?), that’s what they’re talking about: The Conservative “baseline” spending forecast projects annual spending growth of 3%. (That is, that’s what spending would be, without the $20-billion in additional spending the Conservatives have promised. So actual spending under the Conservatives would grow rather faster than that.)

You don’t often see the issue framed that way. Instead, the Liberals talk about a ”$50-billion black hole,” accusing the Tories of inflating their estimates of anticipated federal surpluses over the next five years by that amount. Several commentators have taken up the cry: not only the Toronto Star (“Harper Trickery Creates Illusions”), but also The Globe and Mail (“The Conservatives’ Magic New Surplus”). “If Mr. Harper’s conveniently rosy estimate is recklessly low,” the Globe editorialized, “a Conservative government will have to slash spending in order not to steer this country back into the red.” That, or renege on its promised $37-billion in tax cuts.

How the Liberals came up with $50-billion is a bit of a mystery. The Conservatives project surpluses of $87-billion over five years; the Liberals put it at $43-billion. So the gap would appear to be $44-billion, not $50-billion. Perhaps they mean that, since the Liberal numbers are based on the five years beginning next year, while the Tories’ five-year plan begins this year, the difference between the plans is slightly understated: as surpluses tend to grow over time, the Conservative surplus forecast is somewhat smaller than it would be if it used the same starting point as the Liberals.

Fine: Say it’s $50-billion. That sounds like a lot of money—until you remember that’s over five years, a period in which both parties plan to spend more than $1-trillion. Nor is any “magic” or “trickery” required to explain how the discrepancy arises. It hasn’t anything to do with forecasts of economic growth, or revenues, or interest rates: both parties use the same assumptions here, ie. those in the budget. Rather, it’s due entirely to the difference in the two parties’ baseline spending forecasts. How big a difference? The Tories, as I mentioned, project spending will grow by 3% per annum. And the Liberals? “We expect federal spending—before including any expenditures in the Liberal platform—to grow at just under 4% on average over the [next] five years.” Three per cent versus “just under 4%”—the difference, so we are to believe, between Liberal Paradise and Conservative Hell.

The Conservatives haven’t done themselves any favours by putting the whole of the difference down to Liberal “padding.” This sounds dubious and probably is: though it’s true that Liberal budgets have tended to overstated spending each year in the past, that does not mean they are necessarily doing so now. Except … all the parties assume some degree of Liberal padding. The Tories figure it’s $44-billion. The NDP puts it at $30-billion. And the Liberals? “We will achieve a cumulative total of at least $12-billion of ‘reinvestment savings’ over five years.”

So let’s take the lowest of the three: the Liberals’ own $12-billion estimate of how much needless spending they have packed into their forecasts. That shrinks the Tory “black hole” to $38-billion. The Conservatives, for their part, have identified $14-billion in spending cuts over the same time frame, to come entirely out of business subsidies. So we’re down to $24-billion. But the Tory plan also builds in much more wiggle room than the Liberals’. Where the Liberals allow only $3-billion a year, or $15-billion in total, for “prudence,” the Conservatives leave fully $29-billion, a third of their projected surpluses, unallocated. So the gap has now shrunk to, at most, $10-billion. Over five years.

The notion that the Conservatives could not find another $2-billion in savings, out of annual program spending in excess of $160-billion, is simply risible—especially after the wild expansion in spending of recent years. (And if they didn’t? If instead we ran a deficit of $2-billion a year—on an economy of more than $1.2 trillion—then what? We all turn into pumpkins?) Certainly it does not warrant alarmist predictions of irreparable cuts in social programs, to say nothing of colder winters.

Here again, however, the Tories are their own worst enemies: By their coy refusal to commit themselves to any spending cuts, beyond the risk-free pledge to “end corporate welfare as we know it,” they free their opponents’ imaginations to run wild. I don’t worry they’ll run deficits, or renege on their tax cuts. But would it kill them to let the public in on their plans for spending?