Japan is attempting to lift its self-imposed ban on the right to exercise collective self-defense with its military allies, while nudging its purely defensive forces toward a full-fledged military through extensive joint exercises, observers have warned.

The right to collective self-defense, if included in a revision of Japan's national defense policy guidelines, would drive the country away from its pacifist Constitution and pose a threat to regional stability, they said.

The observers made the remarks after Japanese Self-Defense Forces started their first joint naval exercises with Poland in waters off the Baltic Sea on Saturday. It is the latest in a series of joint exercises Japan has conducted over the past three months with various countries, including its ally the United States and Mongolia.

From Monday through Friday, Japan will participate in a multinational air force drill hosted by US Pacific Air Forces in Alaska.

"Constitutional revision is not easy, so the Abe administration aims to start breaking the post-war shackles by engaging the right to self-defense during these exercises," said Li Xiushi, a senior researcher on Japanese studies at the Shanghai Institutes for International Studies.

The right to collective self-defense, in international law, means the right of any member of an alliance to receive military assistance from other members in response to an attack. The pacifist Japanese Constitution, however, does not identify Japan as having this right.

Changing attitude

After the Sept 11, 2001 terrorist attacks, the US asked Japan to exercise that right many times. Tokyo's response was a chilly one, but its attitude has changed since September, in light of escalating tensions between China and Japan over the Diaoyu Islands.

"Japan had been concerned about being dragged into US wars in Iraq and Afghanistan, but now the conservative government wants to flex its muscles at China with a more robust military," Li said.

Ruan Zongze, deputy head of the China Institute of International Studies, also said Washington, faced with defense budget cuts and a strategic rebalance in the Asia-Pacific, is increasingly eager that Japan can play a more active role in the security alliance, while Tokyo hopes to strengthen its bargaining power with China, backed by the US.

In June, Japan and the US held a series of unprecedented joint drills, code-named Dawn Blitz, off the coast of California, with a specific aim — a joint amphibious assault on an island after it has been seized by a small, but heavily armed, invading force.

The following month, Japan and the US held a joint drill involving naval vessels and 16 fighter aircraft in the airspace and waters off Hokkaido, the northernmost of Japan's four main islands, lying less than 800 kilometers from the waters where the China-Russia military exercise Joint Sea 2013 was held.

Meng Xiangqing, deputy director of the Strategic Research Institute at the National Defense University of the People's Liberation Army, said such joint exercises with clear targets and conditions simulating real combat scenarios are exactly what Tokyo wants. They could exert pressure on China and accelerate the process of normalizing Japan's military forces.

Ruan said the US and Japan will stage more exercises, but Washington is likely to curb the growing right-wing forces in Japan, as regional instability is not in line with US interests.

But Li warned that besides the US, Japanese Prime Minister Shinzo Abe has also attempted to win allies among other maritime nations, including the Philippines and India, with the aim of containing China.