The last thing many Koreans want to see is Japanese soldiers setting foot on this soil again. They shudder at the mere thought of Japanese boots here as it brings back memories of Japan’s ruthless colonial rule.

To their dismay, however, the specter of Japanese troops being deployed here has loomed, as Tokyo is seeking, with the full backing of the United States, to lift a self-imposed ban on collective self-defense.

The United Nations Charter declares that each member country has the inherent right of collective or individual self-defense. A country exercises the right of collective self-defense when its ally is under attack. Even if it is not directly attacked, it can use military force to defend the ally.

Suppose an armed conflict occurred between the two Koreas. The concept of collective self-defense calls for Japan to send troops to support U.S. forces stationed here, given that Tokyo is Washington’s staunch ally.

Thus far, however, the Tokyo government has denied itself the right of collective self-defense under its war-renouncing constitution. While the constitution prescribes a “defense-only defense” posture, the collective self-defense concept could force Japan to engage in offensive military operations overseas.

Yet the incumbent Abe administration is pushing hard to throw away the self-imposed restraint. And Washington is supportive of Tokyo’s controversial move. Recently, the two allies agreed to upgrade their defense cooperation guidelines to help Tokyo reclaim its right and beef up its military.

The agreement is cause for deep concern here as it encourages Japan to accelerate its military buildup. To its neighbors, a militarily powerful Japan is a serious security threat as Tokyo has failed to convince them that it has completely departed from its militarist past.

For one thing, Japan is engaged in territorial disputes with its neighbors, which suggests it has not abandoned territorial ambitions. What’s more, it has never sought forgiveness from its colonial victims based on true repentance for the atrocities it committed.

Despite such concerns, the Seoul government has decided not to oppose Japan’s push for collective self-defense. The decision is practical. After all, Japan is pursuing a right that every U.N. member country is entitled to. Furthermore, Seoul has few effective ways to stop Japan, especially as it is backed by the U.S. and other Western countries, including the United Kingdom and Australia.

Yet this does not mean that Seoul should unconditionally allow Tokyo to send troops here, in the event of an armed conflict, to support U.S. forces. Doing so would be to give up Korea’s sovereign control over its territory.

So the Seoul government has made it clear that Japan should obtain Seoul’s prior approval even if an emergency on the Korean Peninsula justifies its exercise of the right of collective self-defense.

A high-ranking Seoul official visiting Washington has conveyed this position to U.S. officials, urging them to reflect it when they rewrite the U.S.-Japan defense cooperation guidelines.

It is only just that Korea asserts its sovereignty. Washington should respect its stance. It also needs to realize that helping Japan build up its military is no way to enhance security in this region. It would merely trigger an unnecessary regional arms race.

Japan also needs to understand that increasing military spending could be a slippery slope to ruin. No country can prosper without winning trust and respect from its neighbors.