Thursday's intervention in currency markets by the government clearly illustrated their fear that the economy could collapse unless they take action.
The world's third-biggest economy was already under serious downward pressure from the massive earthquake and tsunami in March, which disrupted production and exports and triggered meltdowns at a nuclear power plant.
The intervention, the exact size of which is unknown, apparently succeeded in halting the yen's surge to record levels. But a prevailing view is that the respite will be short-lived and authorities will have to take additional steps to keep the economy on a recovery track from the catastrophe.