I was asked a few months back what we should be calling the Japanese political order in the aftermath of the July House of Councillors election, whether it is indeed the return of the "1.5 Party System" of old. The phrase "1.5 Party System" is a demeaning* and easily apprehended international version of what was domestically called "the 1955 System," after the year the two factions of the Socialists on the left and the Liberal Party and the Japan Democratic Party on the right merged to form two large left/right divide parties, with the right dominant due to the left's division into Socialist and Communist camps. I responded that a better term for the current situation would be a 1.0 Party System. Under the 1955 system, the Socialists could tie up Diet business in a serious way and had to be paid off to an extent the term "1.5 Party System" leaves unclear. "1.5 Party System" indeed undersells the political threat that the Socialists posed (which the LDP neutralized in a whole host of shoddy ways, including absurd levels of disproportion in between rural and urban voting districts). However, the "0.5" in the "1.5" does give the Socialists at least some heft -- which they had.
After last year's House of Representatives election and the July election the rump opposition parties in the Diet are little more than confused noise machines without any power to foment change. Hence my suggestion of a "1.0 System" moniker.
The image of an utterly powerless opposition (the 0 in the 1.0 expression) is obviously an exaggeration. The general concept is not, however, entirely without merit. Leadership of Japan's small but dogged anti-nuclear power and anti-secrecy bill forces, the current most prominent movements challenging the government's attempts to sweep problems under the rug and move on, comes almost entirely from outside the Diet.
I have been and will continue using the 1.0 System expression, having possibly coined it. However, one sees in the news media the indigenous expression ikkyo tajaku (一強多弱 - "one strong, many weak"), an expansion of the standard expression ikkyo meaning "dominant." I have seen the four character compound used on NHK and I think TBS network broadcasts. Here is a letter to editor of The Asahi Shimbun that uses the phrase, though the first character is replaced by the Arabic numeral 1.
When written in kanji the expression ikkyo tajaku is both visually arresting and easily understood. However, what is/would be the elegant and succint English translation?
* Speaking of demeaning, why did the author insert a denigration of Japanese tech praxis in this article on South Korean reverse engineering of U.S. military technology?