In all the past global economic recessions, central banks would usually step in and stimulate/ prop up the economy with loose monetary policies. Governments would also implement certain fiscal policies and even extreme measures (bailout) to help businesses to survive a sharp downturn.
Ben Bernanke cut interest rates from more than 5% to 0% in the previous crisis and kept it that way over 7 years. The world also enjoyed 3 rounds of QE. Seeing the effectiveness of these 2 measures, major central banks in Europe and Asia follow suit. Everyone kept interest rates low and carried out their versions of QE since 2008.
Unfortunately, since interest rates are already low, Janet Yellen has very little left to manoeuvre. The best she can do is to either postpone further hikes or maybe even cut it back down to 0%. Worst still, QE3 showed us that printing huge amounts of money loses its effectiveness the more ......