Yasuo Fukuda and his Cabinet are sinking, and political analysts say the prime minister's condition is critical. So this would seem like the perfect time for the Democratic Party of Japan to pounce.
Lawmakers in the DPJ, the largest opposition force, have repeatedly stressed their intention to corner Fukuda into dissolving the Lower House and calling a snap election.
But instead of seizing the chance to submit a censure motion against the prime minister in the Upper House, which is controlled by the opposition, the DPJ has opted to take the more conventional approach of fighting the Liberal Democratic Party openly in the Diet.