One pillar is, of course, submitting a host of legislation to the Upper House. Sankei notes that in at least one case, the political funds control law, Mr. Ozawa is trying to break the LDP-Komeito coalition — but the daylight between the LDP and Komeito on this and other issues may be shrinking as Mr. Fukuda sets about repairing a fundamental prop of the current government that was woefully undermined by Mr. Abe.
The second two pillars are more obstructionist, concerning the use of parliamentary investigative rights and censure motions (and nixing personnel decisions) in the Upper House.
The former is the key to the DPJ's making the Upper House the place where government policies go to die (or at least gather dust). The investigative powers will give the DPJ the power to request documents and call witnesses, at least in the committees it oversees. To delay government legislation and to undermine the effectiveness of the Lower House supermajority — cumbersome to have to wait two months to pass each bill, after all — it will undoubtedly call witness after witness.
On personnel questions, the DPJ can throw a spanner into the works by nixing personnel appointments that require the approval of both houses, such as the presidency of the Bank of Japan. As for censure motions, the DPJ had considered bringing a censure motion against Mr. Abe, but he resigned too early into the Diet session for the DPJ to deliver on this threat. The article suggests that the DPJ recognizes that at this point a censure motion isn't a realistic option; for the moment, they're stuck with Mr. Fukuda.
But for that reason I'm not clear on what Mr. Ozawa is aiming to accomplish. The DPJ cannot pass laws without the government's approval; the government can, if necessary, pass laws without the Upper House. With his "legislative storm," Mr. Ozawa may be trying to call the government's bluff: "You say you want to cooperate — well, how about these laws?" But what if Mr. Fukuda and the LDP cooperate? I think the LDP probably has the most to gain from cooperation, hence the persistent calls for a grand coalition. The DPJ, meanwhile, wants the government to appear out of touch and lethargic. In game theory terms, under cooperation the DPJ doesn't exactly "lose," but the payoff is smaller — it gains less than it would in a situation where the government is inactive, while the DPJ is actively passing legislation in the Upper House. But that scenario seems to be increasingly unlikely. Mr. Fukuda is certainly aware of what's at stake, and will do whatever it takes to regain the public trust, including swallowing what for some LDP members is the bitter pill of cooperation with the DPJ.
Is Mr. Ozawa certain that he has the public behind him? Or are the Japanese people weary and actually willing to give Mr. Fukuda a chance to succeed? If the latter, the DPJ's use of obstructionist tools in the hope of triggering an early election — Mr. Ozawa's "Jiminto delenda est" strategy — could quite easily backfire.
I am by no means saying that the DPJ shouldn't be submitting legislation to the Diet; having won its near-majority, of course it should. But the question is one of intent. Is the DPJ submitting legislation simply to pressure the government, or is it submitting legislation because it actually wants to see laws passed? If the latter, it has no choice but to cooperate with the LDP-Komeito coalition, meaning, like I argued before, that if the DPJ actually wants positive legislative achievements before the next election, it has no choice but to cooperate with the government, which will paradoxically lessen the electoral significance of said legislative achievements.