As the U.S. government takes on an ever-expanding role as lender and investor for the nation's economy, financial firms find themselves watching Washington much more closely than Wall Street. The world's biggest bond fund, Pimco, used to measure investments against five criteria. Now they have one more, the consequences of any change in federal policy. "In the old days, Washington was refereeing from the sideline," said Mohammed A. el-Erian, CEO at Pimco. "In the new world we're going toward, not only is Washington refereeing from the field, but it is also in some respects a player as well."