Why are Russian bombers buzzing Japanese airspace?

Japanese fighter planes scrambled, and Tokyo foreign policy-makers scratched their heads in confusion, after two huge Russian bombers provocatively skirted Japan's airspace for the second time in as many days Sunday, barely two weeks after top Russian and Japanese officials had finished a round of unprecedented negotiations aimed at boosting military and security cooperation between the two countries.

Japan's Air Force went to high alert when the two lumbering Tu-95 strategic bombers – roughly equivalent to US B-52s – appeared on radar screens over the Pacific Ocean Sunday, and flew the full length of the Japanese archipelago before disappearing into Russian airspace near Sakhalin Island. On Saturday, a Russian Tu-142 long-range antisubmarine aircraft triggered a similar response when it approached Japanese airspace. On neither occasion did the aircraft cross into Japanese territory.

Experts say encounters like this are fairly common. The Japanese Defense Ministry has reported 105 cases when it scrambled fighters to intercept incoming Russian aircraft between July and September of this year alone, a huge increase over the previous three-month period.

But last weekend's incidents appear out of tune with the first-ever high level talks aimed at boosting military trust between the two countries, held in Tokyo earlier this month between the Russian foreign and defense ministers and their Japanese counterparts. The talks were declared a success, with both sides agreeing to engage in deeper dialogue, exchange security information, and even hold joint military exercises.

"To boost cooperation in the field of security, and not just in the field of economic and people exchanges, means that we are improving overall Japan-Russia ties," Japanese Foreign Minister Fumio Kishida told a news conference on Nov 2.

"Cooperation between Japan and Russia, as key players in the Pacific Ocean region, is important for fortifying peace and stability in the region," he added.

Some observers say the unprecedented new dialogue could even lead to an eventual breakthrough in the Russo-Japanese deadlock over the disputed Kuril Islands that's lasted since the end of World War II.

"There is absolutely no reason for anyone to want to make some sort of military demonstration to Japan at this point. They've been holding talks, and quite successful ones, about enhancing mutual security," says Alexander Golts, military expert with the online journal Yezhednevny Zhurnal.

"So, it seems likely this is just a coincidence. The left hand doesn't know what the right hand is doing. It happens, and it's probably the explanation here," he says.

Tensions have flared on and off over the Kuril Islands, which the Soviet Union occupied in 1945, and the issue is still capable of  inflaming nationalists on both sides.

But over the past year, Russian President Vladimir Putin has moved to find a compromise on the issue in hopes it will lead, after almost 70 years, to the signing of a peace treaty between Russia and Japan. That could unlock the Japanese investment and technical cooperation that Russia desperately needs to develop its Pacific territories, which are rich in natural resources but poor in infrastructure.

Experts say that however ill-timed the Russian bomber flights may seem, they are unlikely to disrupt the diplomatic process.

"These military flights are perfectly normal. Everybody is doing it," says Valery Kistanov, a Japan expert with the official Institute of the Far East in Moscow.

"Nobody violates anybody's airspace, so there is really nothing to this. The fact that Japanese fighters take to the air is also routine. Russian-Japanese relations are improving lately, a full-scale dialogue is on, and that's the real story here."