The trove of statistics and reports released last week point to an economy on the mend.

U.S. homebuilders are feeling increasingly optimistic about their battered industry. Consumer spending is on the rise. America's factories are humming again. Stocks, in turn, have been climbing.

Not so fast, cautions Bruce Bittles, chief investment strategist for the wealth management firm Robert W. Baird & Co. and a devil's advocate.

It's not that Bittles disagrees with the upbeat but backward-looking numbers coming out of Washington lately.

"Things are starting to feel better, and the stock market is a representation of that," he said during an hourlong talk in Charleston last week for Milwaukee-based Baird's local advisers and clients.

But peering down the road to recovery, the veteran market watcher has spotted some dangerous potholes ahead. He's more than a bit "suspect" that the fragile rebound will have legs.

"I'm very skeptical about the next year or two," he said. "I don't think we're out of this yet."

One big concern for Bittles is consumer spending, which drives two-thirds of the economy. While shoppers have been feeling more confident and throwing more money around lately, especially on big-ticket items such as cars, he's worried that the spree will be short-lived.

Overall wages have been flat for 18 months and in the red for the past nine months when inflation is factored in. That suggests that personal savings are helping fuel the spending uptick.

"That's never a good sign," Bittles said.

The flip side of that same coin is Americans need to save more, as they have through much of the downturn, he added.

Four-letter word

Market experts such as Bittles often are asked by investors what keeps them awake at night.

The threat of war? Inflation? A spike in oil prices? All valid concerns, for sure. But Bittles' biggest fear goes to the issue that brought the global financial system to its knees in the first place.

"It's the excess debt in all corners of the economy that keeps me up at night," he said.

Bittles described debt as "that four-letter word," literally and figuratively. He called the growing stockpile of taxpayer IOUs "an anchor" on growth because the mounting cost of paying it down "saps everything out of the economy."

"That's why we can't have a sustained boom like we have in years past," he said.

Greece is the current poster child for spending more than it could pay back, but Bittles says the U.S. is heading down the same path. Where it ends, no one knows.

"Nothing's been addressed," said Bittles, who is based in Nashville. "We just keep kicking the can down the road, but the can is getting heavy."

How heavy? The estimated $15.3 trillion national debt has swelled to about 9 percent of the Gross Domestic Product. That's on par with Spain.

"And we're worried about Spain," Bittles marveled.

Game over?

For all his skepticism, Bittles holds out hope that the debt crisis will get addressed in due time, saying the so-called Great Recession changed the mood of the country.

"I think the game is over," he said.

He noted that households tightened their belts when the economy tanked, as did businesses.

"Individuals get it. Corporations get it," he said.

Next up were state and local governments.

Now, it's Uncle Sam's turn to slay the debt monster.

Bittles predicted that meaningful reforms could gain traction within three years.

"It's not going to happen overnight," he said.

In fact, it's going to get worse before it gets better. Case in point: Congress last week agreed to extend the temporary cuts to the payroll tax, which helps pay for Social Security. At the same time, an aging U.S. population is driving 10,000 people a day into that federal safety net.

"It doesn't make any sense," Bittles said.

But the issue isn't going away.

Bittles said the powers-that-be in Washington, like a drunk who's ready to sober up, are finally taking the first small but crucial step to deal with it:

"Admitting you have a problem."