Twice before, Prime Minister Shinzo Abe has backed away from the sort of sales tax hike that toppled at least one predecessor. Now, he faces the same dilemma again.

In five months Japan is set to raise the levy to 10 percent from the current 8 percent to help ease the developed world's biggest debt load. If he postpones the move, it would indicate his Abenomics policies have failed to generate the stable growth he promised more than six years ago.

But he could face a similar result if he follows through, buckles the economy and pushes inflation back down to zero.