THE question on whether or not the Chinese aircraft carrier CV-16 Liaoning passed through Sibutu Strait in Tawi-Tawi is a disturbing issue for the simple reason that sincerity and truth matters between Philippine-China relations.

Sibutu Strait lies between Tawi-Tawi’s main island and Sibutu Island, which is part of Tawi-Tawi Province. Although part of the country’s maritime territory, the strait has been declared an international sea lane where foreign commercial ships have the right of innocent passage. The latter is a concept in the law of the sea that allows for a vessel to pass through the territorial waters of another state, subject to certain restrictions. Part of these restrictions is how China’s only aircraft carrier became an issue.

While it is true that under international maritime law commercial vessels may sail through this passage without informing the Philippine government, the same does not apply however to navy ships from any foreign nation, including China, whose military presence in the West Philippine Sea is palpable because of its nine-dash line claim that encircles as much as 90 percent of the South China Sea. As a rule, military vessels that pass through our territory ask for diplomatic clearance.

But what is disturbing/unnerving about China’s People’s Liberation Army Navy warships is that it has been navigating this international sea lane with impunity, as if the passage belongs to China, thus, prompting Supreme Court Senior Associate Justice Antonio Carpio to criticize China’s “double standard” as it would not have allowed Philippine vessels easy passage in its own waters, or even Philippine waters China claims for itself.

What is ironic about what I describe as “arrogant passage” by the aircraft carrier Liaoning is that the incident was revealed first by Carpio and not by the country’s military authorities who should have known it earlier and protested because of their inherent duty to protect the national security of the country.

Sought for comment, Defense Secretary Delfin Lorenzana apparently was clueless about Carpio’s revelation and even as he consulted Chinese Ambassador Zhao Jianhua about it, the latter denied it, which no doubt raises the question of his sincerity and honesty in his dealings with the Duterte’s government.

After being told that Chinese warships were seen passing through the Sibutu Strait in Tawi-Tawi with its Automatic Identification System intentionally turned off to avoid detection, although still visible by the naked eye, Ambassador Zhao extricated himself by saying that “in the future, we will require those ships to inform the Chinese embassy here in Manila about intended passage in Sibutu.” Isn’t that a clear reaction to an afterthought?