Japan held a peace memorial Tuesday in Hiroshima to mark the 68th anniversary of a US atomic bombing, which caused massive casualties and severe property damage.

On the same day, in a not-so-peaceful ceremony, Japan unveiled at a port near Tokyo the largest warship of its Maritime Self-Defense Force.

The giant vessel was named Izumo, namesake of a Japanese cruiser once used during the invasion of China in the early 20th century.

Although it's called a "helicopter-equipped destroyer," the new vessel, with a length of 248 meters and a weight of 19,500 tons, is much more like an aircraft carrier.

Being able to accommodate 14 helicopters, the ship is also available for the US Osprey tilt-rotor aircraft. With minor modifications, it can be remodeled to a fully-functioning aircraft carrier, which is generally considered as offensive weapons and therefore prohibited by the Japanese constitution.

The Article 9 of Japan's current constitution reads that "land, sea, and air forces, as well as other war potential, will never be maintained."

So launching such a de facto aircraft carrier is in flagrant violation of the pacifist clause, and another alarming sign as the Japanese government is mulling to ditch the pacifist constitution and bolster the country's military forces.

In an earlier provocation which incurred strong protest from both inside Japan and neighboring countries, Japanese Deputy Prime Minister Taro Aso said last week that Japan could "learn from the technique" that Nazi Germany used to alter the Weimar constitution.

The gaffe-prone Japanese politician seemed to suggest that, just as the Nazi regime clandestinely rebuilt a formidable army, Japan could quietly bolster its military without drawing public attention or criticism.

In the eyes of many in the region, the launch of Izumo, namesake of a sunken WWII Japanese warship, and Aso's proposal on picking up Nazi tactics, indicate an attempt to resurrect the skeletons of Japan's inglorious militaristic past.

Thus, there are enough reasons for the international community to be wary of a potential revival of Japan's militarism.

Japan's covert rearmament cause under the disguise of "self-defense" would drag Asian countries into an arms race, threatening the region's stability.

During the Hiroshima peace ceremony, Japanese Prime Minister Abe Shinzo vowed to ensure that "the horror and devastation caused by nuclear weapons are not repeated."

To do so, Japan must reflect upon its history of aggression, stop rearmament, and return to the path of peace.