Despite a lot of analysts thinking exactly the opposite, the National Retail Federation (NRF) predicts that U.S. retail sales growth will outstrip last year???s rate of 3.5 percent and come in at a strapping 3.9 percent. That would mean about $602 billion worth of purchases, according to the world???s largest retail trade association. It also assumes that the federal government shutdown is short-lived. ???But if it continues for an extended period of time, then it certainly could have consequences for the broader economy and for consumer spending and holiday retail sales,??? according to NRF President and CEO Matthew Shay. What???s that mean for investors? Well, instead of plunking down your funds on U.S. retailers ahead of the boost, wait until the government dust-up settles.