A month has passed since the Lower House began deliberations on the government-proposed security legislation. Prime Minister Shinzo Abe's ruling coalition voted this week to extend this Diet session, originally scheduled to end Wednesday, by an unusually long 95 days through Sept. 27 — an indication of his resolve to get the legislation enacted, which he effectively pledged in his April speech to the United States Congress to achieve "by this coming summer."

There is speculation — denied by members of the Abe administration — that the coalition extended the session for such a long period to make sure it can enact the legislation via a revote in the Lower House on the strength of its two-thirds majority even if it gets stuck in the Upper House. However, time spent in the Diet alone won't legitimize the bills. Serious doubts about the proposed legislation have emerged through the Lower House debate, including charges by constitutional scholars and former heads of the Cabinet Legislation Bureau that it is unconstitutional — to which members of the administration have not supplied convincing answers.

The proposed legislation would implement the Abe Cabinet's decision last year to enable Japan to engage in collective self-defense — which past administrations have consistently said is banned under the war-renouncing Constitution — and significantly expand the scope of Self-Defense Forces' overseas missions, including joint operations with the U.S. military.

The administration brushes aside the charges that the legislation is unconstitutional and insists it is consistent with a 1959 Supreme Court ruling that the postwar Constitution does not deny the nation the right to defend itself. Last year's Cabinet decision and the proposed legislation, it says, do not deviate from the position of past governments because the bills would allow Japan to engage in minimal acts of collective self-defense only when the nation's own survival is threatened — unlike the internationally accepted concept of collective self-defense to defend allies from an enemy attack as if it were defending itself.

However, the shakiness of the government's explanation was highlighted when former chiefs of the Cabinet Legislation Bureau — who advised past administrations on the constitutionality of laws while they were in office — spoke at Monday's Lower House session on the proposed bills. Reiichi Miyazaki said Japan engaging in acts of collective self-defense, even in limited ways, runs counter to Article 9 of the Constitution, adding that the Abe administration's move to change the government's established interpretation of the Constitution "ruins (the nation's) legal stability."

The legislation says Japan can take defense action not only in response to an armed attack on Japan but also when an attack on another country with which it has close ties "threatens Japan's survival and poses a clear danger to fundamentally overturn the people's right to life, liberty and pursuit of happiness" and "there is no other appropriate means available to repel the attack." This constitutes the grounds on which the government says Japan will exercise the right to collective self-defense only in minimal ways.

Miyazaki, who was head of the bureau during Abe's first stint as prime minister from 2006 to 2007 and is reported to have rebuffed a request by him back then to change the government's interpretation of the Constitution, said such a condition would not serve as any criterion defining the scope of Japan's overseas military actions. This is because all of the countries that have sent their forces abroad in the name of collective self-defense did so "by saying that (the situation) concerns their own crucial interests," he said.

Masahiro Sakata, Miyazaki's predecessor, noted that acts of collective self-defense in restrictive ways may not be entirely inconsistent with the government's previous interpretation of the Constitution. But he urged this government to make it clear that Japan would take collective self-defensive action only when "there is a clear danger that Japan will come under armed attack."

Sakata also said Japan's participation in a minesweeping operation in the Strait of Hormuz — which Abe repeatedly cites as an example of which the SDF could be deployed in an act of collective self-defense — clearly oversteps the government's previous position. If the government is to say that a halt to crude oil shipments from the Middle East and a fall in Japan's oil reserves threatens the nation's very survival, he said, that would be the same logic that Japan used when it embarked on the invasion of China beginning with the Manchurian Incident of 1931 by saying that crucial national interests were at stake.

These views underline the fundamental concern over the legislation — that the judgment on whether a particular situation "threatens Japan's survival and poses a clear danger to the nation" will be left in the hands of the administration in power.

Abe maintains that he is fully confident of the legitimacy and legality of the proposed legislation. He rebuffs the charges of unconstitutionality from the scholars and former bureaucrats by saying that politicians have a duty to constantly think how much Japan needs to do to defend itself. He also says politicians would be derelict in their duty if they turn a blind eye to changes in international security circumstances and cling to the previous interpretation of the Constitution. Even so, he must let no doubt remain over the legal grounds of such profound legislation.

The administration should realize that the public is not convinced of the bills' constitutional legitimacy. In a Kyodo News poll taken last weekend, 56.7 percent of the respondents said the proposed legislation violates the Constitution, as opposed to 29.2 percent who did not think so. Opposition to the legislation rose 11 percentage points from the previous survey last month to 58.7 percent — against 27.8 percent who support the bills. Nearly 85 percent of the respondents said they do not think the Abe administration has given sufficient explanations about the legislation.

The major change in the nation's postwar defense posture that the legislation would introduce can be instituted only with broad public support and understanding, and only when there is no doubt about its constitutionality.

The administration should not think that time and the ruling bloc's majority is enough to get the proposed legislation through the Diet.