The Bank of Japan, can actually control inflation, because, as we have determined, they control the interest rate. Also, if necessary, the government could raise taxes and run a surplus to diminish inflationary pressures.

But those are moot points, because the problem of Japan for the last 20 years has been deflation, not inflation. Despise that, as you can see in the comments here, there are people that still predict inflation in the future.