GRIM. Serious. Terrifying. Nerve-rattling.

These are the words some prominent American investors and strategists are using to describe the worsening debt crisis in the eurozone and its impact on the global economy.

While growth has been slowing in China and the United States and companies warn about the effect on earnings, there is a mounting sense among the financial community that politicians and markets are operating on two completely different time-lines.

They see a fractured Europe fiddling in the near term, attempting to seal one fissure as another larger one appears while they talk about a five-to-10-year time-frame for real solutions, such as a more fiscally integrated eurozone. They see investors who want solutions in the next few weeks and months or else nations like Spain and Italy could find they cannot borrow at all on capital markets, starting an economic firestorm that would make today's problems seem mild.

Some even suggest markets are taking on shades of the 2008 global crisis, with the potential for a collapse in investor confidence, bank runs in Europe and a seizure for the global financial system.

"History may not repeat but it often rhymes. The fear is that it could be a replay of 2008. The reality is that the potential for a replay of 2008 on steroids is not exactly zero," said Bonnie Baha, portfolio manager at DoubleLine Capital, which oversees US$35 billion. Baha, who is based in Los Angeles, was speaking while visiting Europe last week.

Added financier Steve Rattner, who is the former head of the US auto task force, "We should be terrified about the euro crisis because the Europeans are trying to fix a deeply flawed system with the equivalent of Band-Aid."

And Dan Fuss, vice chairman and portfolio manager at Loomis Sayles, which oversees US$172 billion in assets, sees little reason not to be very worried. "We have uncertainties of the wrong kind. Bringing the political cohesion together has proven to be more difficult than I had thought."

To be sure, while these are the views of highly credible investors, they are not necessarily the mainstream. Most economists and strategists still think Europe will be able to muddle through its problems as it has for the past few years. And while the majority of them see weak growth in the US, they don't expect the economy to slip into a recession.

But most economic pundits were wrong in 2008 when they didn't foresee the financial crisis, and this time around even the optimists have had to pull back their US and global growth expectations in recent months.

The economic crises in global history that have stemmed from excessive debt and financial leverage have proved to be the deepest. And while the US has managed to maintain slow, if steady economic growth, many European countries are dealing with the threat of deep recessions.