well, there's a number of factors.
First of all, the two newbuilds: It really was necessary for ROC to get new ships. However, it was a financial balance act to be able to pay for them. As you might remember, ROC refused to take delivery of "Olympia Explorer" for a year(!) as they claimed the ship didn't meet the standards set in the contract. The German shipyard, Blohm + Voss, vehemently denied that. It turned out that ROC was unable to pay, so they tried to get some more time out of the whole deal to raise funds. Each newbuild was delivered to a newly established U.S. affiliate of ROC. However, ROC did vouch for those companies' financial liquidity. Those two companies were the ones which filed for bankruptcy protection last month.
Then, there's the fact that IMHO ROC made huge mistakes as far as fleet deployment is concerned. Being traditionally focused on the Eastern Mediterranean made them very vulnerable: September 11th, Afghanistan, Iraq - lots of poeple, American passengers in particular, don't want to take cruises in the Eastern Mediterranean. But what did ROC do? Instead of putting their new, very good ships in other markets (e.g. The Baltic or the U.S. East Coast) during the summer months they kept them in the Eastern Mediterranean, where they sometimes sailed with less than 100 passengers. And in The Baltic they used the old "Triton", which is no worthy competition to most other lines operating in the region.
It would be sad to lose such a traditional company (although ROC itself is of course a rather young one), but instead of blaming war, SARS and other factors, the people at ROC's helm should probably see whether they did everything right. IMHO, they didn't!