Prime Minister Junichiro Koizumi's administration is enjoying record high public-approval ratings of more than 80 percent. Television news-programs report daily on the activities of Koizumi as well as Foreign Minister Makiko Tanaka, who has caught the public's fancy as the top female member of his Cabinet. Ratings for live television coverage of Diet sessions have sharply risen. Japanese are in the midst of "Koizumi fever."

The Koizumi Cabinet's public-approval ratings exceeded those for my Cabinet, which took power in 1993. There have been some media reports and commentaries comparing the Koizumi and Hosokawa administrations. They share similarities -- both wrested power from the LDP establishment with their pledges of reform -- but have differences as well.

The Hosokawa Cabinet was the first government in 38 years to oust the Liberal Democratic Party from power. We received public-approval ratings of more than 70 percent, a sign that the Japanese public welcomed the political upheaval.

On the other hand, the Koizumi Cabinet is based on a coalition of the LDP, New Komeito and the New Conservative Party, as was its predecessor, the unpopular Cabinet of Yoshiro Mori. Like the Mori administration, the Koizumi Cabinet includes many members who belong to the LDP's Mori faction. The Koizumi Cabinet retained its predecessor's chief Cabinet secretary and his two deputies.

But Koizumi rose to power by throwing down the gauntlet before the powerful LDP faction headed by former Prime Minister Ryutaro Hashimoto, which had long controlled LDP presidential elections. Power did not change hands from the LDP to an opposition force, but Koizumi crushed the Hashimoto group in his third attempt to win the LDP presidency and change the party's power structure from within. The public welcomed Koizumi's bold action.

The Koizumi Cabinet is similar to my Cabinet in its push for reform. The Koizumi administration advocates reforms "without sanctuaries," while my Cabinet was the first government in the postwar period to call for bold structural reform. I welcome Koizumi's efforts to push for even more drastic reform.

Koizumi is advocating two types of reform. First, he formed a Cabinet without selecting ministerial candidates put up by major LDP factions, he asked potential LDP candidates for the Upper House election in July to sever ties with their factions and he moved to improve relations with the media. Going against the wishes of bureaucrats, who wanted to save face, he also decided against appealing a landmark court ruling ordering compensation for Hansen's disease patients, who were forced to spend decades in social isolation. These actions did not entail any social costs.

The second type of reform relates to Koizumi's proposals to privatize the postal service, reallocate revenues from certain taxes for uses other than law-mandated ones, overhaul the system for tax allocation to local governments and overhaul government-financed public corporations. Koizumi has pledged to implement these plans, which entail high social costs, but has not announced specifics. His reputation as a government leader will depend on his ability to implement this type of reform.

The obvious difference between the Koizumi administration and my own is that the former is an LDP-led government while mine was a non-LDP government. Koizumi is trying to change Japan from within, using the governing LDP as a leverage; I tried to do the same from without.

My colleagues and I worked hard to protect the government from desperate attacks by the LDP, which remained a force to be reckoned with after turning into an opposition party. We also had to maintain the fragile unity of the eight political groups that made up my administration. We were forced to depend on the bureaucracy to run the government, since we had little experience in such affairs.

I now feel that I remained too much on the defensive. Perhaps my administration should have made stronger appeals to the public about its objectives.

Given the weakness of the opposition, the Koizumi administration should have no fears of the ruling force disintegrating due to a lack of unity. It need not worry too much about steering the Diet and should have no trouble coming up with bold policy initiatives. On the other hand, the Koizumi administration could be affected by power struggles and resistance to the government within the LDP. So far, thanks to the strong public support he enjoys, Koizumi has succeeded in quelling intra-LDP dissent. The real test will come later.

I would advise Koizumi to establish a framework for reform as soon as possible, while he still enjoys strong public support, since the LDP tends to deter reform. He should not try to please everybody.

In his plan to reform government-backed corporations, Koizumi should target symbolic organizations to break strong resistance. He should not seek a long term in office. He is likely to succeed if he pushes for bold, quick reform before running out of steam.

He should also have bureaucrats follow his orders. He could well run into bureaucratic resistance, but he should create a system of establishing policies and making final judgments on his own.

His proposals to privatize postal services, reallocate certain tax revenues for uses other than legally mandated ones and overhaul government-financed corporations involve the Finance Ministry. Koizumi should try to avoid getting involved in disputes between the Finance Ministry and other government departments over this issue. His proposed reforms "without sanctuaries" should not conclude in a balancing of fiscal expenditures and revenues under the leadership of the Finance Ministry.

It is up to Koizumi to turn the LDP into what he calls "a party of reform." His moment of truth is now, not in the coming months.