SINGAPORE — A year ago, before the financial crisis started to bite hard, the United States and Europe were worried that Asian and Middle East nations, armed with a mighty war chest of surplus foreign exchange reserves from their exports of manufactured goods and oil, would gobble up so-called strategic assets in the West.

Then, as the credit crunch turned into an economic recession, the state-owned investment companies, known as sovereign wealth funds (SWFs), found that they were being hailed as saviors of tottering banks and ailing firms in America and Europe.

Today, like many private institutional investors, the SWFs are saddled with huge paper losses and reviewing what to do — just as some Japanese lawmakers and politicians are considering whether Japan should join dozens of other countries with bulging foreign exchange reserves and set up a sovereign fund.