US President Bill Clinton, jettisoning diplomatic conventions, has intervened in Japanese domestic politics in the run-up to the July 18 general election, calculating that he can assist the winds of political change blowing through the country. Mr Clinton could be taking a grave risk since public opinion polls timed to coincide with the Group of Seven summit in Tokyo, clearly show Japanese and American attitudes towards each other are moving from friendship towards reviving former antagonism. His moves were ostensibly meant to be neutral, of course. In his joint press conference with Japanese Prime Minister Kiichi Miyazawa on Tuesday, Mr Clinton went out of his way to praise Mr Miyazawa's qualities of ''energy and engagement and openness'', which he had displayed in US-Japan trade negotiations. But with Mr Miyazawa's approval rating at 6.7 per cent - according to a pre-summit poll by the right-wing daily Sankei Shimbun - Mr Clinton's kind words had all the resonance of a valedictory. Many Japanese will have seen his remarks to Mr Miyazawa as the tatemae (outward show), while the honne (inner meaning) was his behaviour and body language at a reception given at the US Ambassador's residence in Tokyo. There, as Mr Clinton briefly but animatedly chatted with two leading dissidents - former Liberal Democratic Party (LDP) finance minister Tsutomu Hata, founder of the newly formed Shinseito party, and former prefectural governor Morihiro Hosokawa - he lentweight to his remarks to the 30 or 40 top Japanese politicians at the reception. Mr Clinton said: ''We come here with outstretched hands, and hope that all the ferment and change and political debate going on in Japan will be a very positive thing for your people and our relationship.'' Mr Clinton has extolled the virtues of accepting change at least four times recently. ''Japan is going through a period of political transition,'' he told the 15 million-circulation Yomiuri Shimbun. ''I hope the Japanese people will view it with excitement and interest, not with too much concern. This is a normal thing for a democracy.'' Unexceptional words, perhaps, except when it is remembered that Japan's deeply conservative voters have never had the experience of voting a ruling party out of office - and may well be worried that ending the LDP's long reign is an unwise move. Mr Clinton's stress on change could backfire. The risk lies in numerous public opinion polls which show a sharp increase in US-Japanese distrust, and in dislike for the President himself. It would be consistent with these attitudes for Japanese voters to resent and reject Mr Clinton's polite suggestion to them to try voting for someone else for a change. But they may not do so in great numbers for three reasons. First, for four days this week Japanese television viewers are seeing Mr Clinton in person - and not through the filter of often critical official or press comment. ''The mere sight, for us, of that young, dynamic man standing next to our old and tired leader is downright subversive,'' as one Japanese academic put it. Secondly, Mr Clinton has carefully modulated his message from the initial slightly abrasive tone he adopted soon after the Miyazawa administration was toppled. And he could well be tapping into the undoubted reservoir of goodwill for the US still held by many Japanese. It was an appropriate symbol that the room in which he shook hands with Mr Hata and Mr Hosokawa was the same one where another American once instituted change in Japan - it was where General Douglas MacArthur received Emperor Hirohito in the wake of Japan's defeat in 1945.