The stock market posted it's biggest one day gain since March 2009 yesterday, soaring nearly 500 points. You'd think that just about anyone with a retirement account, who has witnessed a couple of painful years of stagnation or worse, would be jumping up and down with job.

Yet I'd urge fellow account holders to be a little more cautious while assessing this news. The Wall Street Journal reports that there were three reasons for yesterday's big jump. One of them—the Department of Labor's report of stronger-than-expected private sector hiring—is truly good news and a legitimate reason for optimism. If companies are assessing their business models and deciding that they expect more demand in the future and therefore need to hire more workers, that's a sign that we may be climbing out of recession for real this time, and that companies long-term prospects for profitability are improving, which should make their stocks more valuable.

Yet the other reasons for the stock surges all revolve around government policy: Central banks around the globe announced they will make it cheaper to borrow money, hoping to easy the pressure on Europe, and China is lowering requirements for bank reserves also to all facilitate more borrowing. This makes it a little less likely that the Euro will collapse in the very near term and that banks will be unable to meet their bills.

That's great…except that it doesn't actually address the fundamental problem of countries (and banks) having too much debt and too few resources to pay them back. It may put-off the date at which the proverbial chickens come home to roost, but the chickens are all still out there.

Americans should also be concerned about how government policy no longer seems to simply play a role in stock market prices and asset values. Increasingly government policy seems to be the driver of these matters. Slashing interest rates is great for stock holders, but bad news for bondholders. For years, government has seemed happy to try to juice the stock market, even at a cost to some economic fundamentals. I've written before about the danger of government picking winners and losers among companies and industries, which inevitably becomes corrupt and political. The same goes double when government is picking winners and losers among classes of financial instruments.

We want a stock market that's growing because the global economy is growing, because people are becoming more productive and prosperous so there is reason to expect greater profitability in the future. It's not good news when government manipulates the market to send stock prices up, since that's really just manipulation that someone—and more likely than not that someone will be the economy generally—will pay a price for eventually.