As expected, the Korea Confederation of Trade Unions has withdrawn its support for the embattled Unified Progressive Party, accelerating its split into two political groups.

In May, the militant umbrella labor group threatened to stop backing the party should it fail to expel Reps. Lee Seok-ki and Kim Jae-yeon, who have been found to have become the party’s proportional representation candidates for the April parliamentary election through a rigged primary.

Yet the party failed last month to pass a motion on ousting the two controversial lawmakers due to resistance from the pro-North Korea National Liberation faction. Under this situation, the KCTU’s action was only natural.

The KCTU is the single largest support base for the progressive party. Of the UPP’s 75,000 due-paying members with voting rights, 46 percent or about 35,000 belong to the labor organization.

The labor group’s decision to retract support for the UPP does not mean an immediate defection of all its members from the party. Some KCTU members who support the National Liberation faction will stay. Yet a large majority of the confederation’s members are expected to break away from it.

This will speed up the secession of the party’s reform-minded anti-NL groups, who are moving to set up a new progressive party. The labor group, however, did not expressly declare its support for the new envisioned party.

The NL faction, which is responsible for the party’s downfall, still refuses to face up to reality. If reform-minded groups break away en masse, the UPP will degenerate into a party consisting only of North Korea sympathizers.

This means it will lose its reason for existence as a political party. There is no justification for a party that negates the legitimacy of South Korea and follows the logic of North Korea. Such a political party should be disbanded.

The reformist groups, for their part, need to base the envisioned progressive party on the values that resonate with the public. They should throw away old ideas that have lost currency and present a new vision for Korean society.

The KCTU also needs to do deep soul searching. As a powerful labor group, it has an important role to play in promoting worker welfare and shaping the nation’s progressive politics. Yet it recently raised many eyebrows by showing a strong pro-North Korea tendency during a rally. If the KCTU fails to renew its outdated view of Korean society, it will neither be able to lead the labor movement nor energize progressive politics.