The Democratic Party of Japan and the Liberal Party see each other as partners in a future government. Yet their on-and-off merger talks, which began half a year ago, seem to have produced no meaningful progress. Prospects for their unification receded further into the background Monday when Liberal Party leader Ichiro Ozawa, in a meeting with DPJ head Naoto Kan, rejected plans to form a parliamentary faction prior to a merger.

The collapse of the talks is unfortunate, although it is not surprising given a lack of policy agreement and mutual trust. The DPJ, the largest opposition party, is plagued by internal discord stemming from its diverse makeup. The Liberal Party, headed by a charismatic leader who advocates a proactive security policy, is viewed with skepticism by moderate members of the DPJ.

Still, the idea of consolidating the two parties makes sense. Forming a parliamentary faction would be like making an engagement prior to marriage. However, Mr. Ozawa rejected the plan for a reason that seemed less than convincing: The plan did not say when the two parties would merge. It appears that in his eagerness to set a date he might have ruined the chances of marriage itself.