bush responded to the early signs of economic problems with lump-sum tax rebates and other stimulative measures in the economic stimulus act of 2008. in march 2008, bear stearns, a major us investment bank heavily invested in subprime mortgage derivatives, began to go under. rumors of low cash reserves dragged bear's stock price down while lenders to bear began to withdraw their cash. the federal reserve funneled an emergency loan to bear through jp morgan chase. (as an investment bank, bear could not borrow from the fed but jp morgan chase, a commercial bank, could).