A Harvard economist has said that the high rate of inflation currently plaguing the United States has positioned the economy on a “knife edge,” and it’s difficult to see how the Fed’s indecisive wait-and-see stance will bring it back on track.Kenneth Rogoff said on Fox Business’s “Mornings with Maria” that the recovery is “still pretty good, but we certainly have inflation which is almost eye-popping, over 6 percent.” While the core inflation is lower, he said, these are “stunning numbers from just a few years ago.”The Fed, meanwhile, claims that the inflation is temporary, but Rogoff said that if the...