Has Japan'spolitical paralysis finally lifted? The agreement last week between the government and leading opposition parties to double the consumption tax - the sales tax - from 5% to 10% by 2015 suggests that it has.

But there is a real risk that the government will mistake this measure for the end of the economic reform process. In fact, it is - or should be - only the beginning.

By virtually any measure, official Japanese debt is the highest in the world. The total outstanding volume of Japanese government bonds is an almost unfathomable $9 trillion, just below the $10.5 trillion in outstanding debt for the 17-country Eurozone, which has more than triple the population.

So grim hasJapan'sfiscal position become that bond issuance now exceeds tax revenue. Taxes cover less than half of government spending. And last year's earthquake, tsunami and nuclear disaster only made a grim fiscal picture worse by requiring huge new spending on reconstruction. Japan issued a record $693.5 billion, or 12% of nominal GDP, in government bonds during the last fiscal year.

Japan's fiscal problems, of course, have been mounting for decades. Indeed, annual tax revenue has fallen 30% since the country's property bubble burst in 1989, owing to slow growth and deflation. Tax cuts implemented as stimulus measures during the 1990s recession also played a subsidiary role.