Admiral John C. Aquilino gave an exclusive interview to the Associated Press while onboard a Navy reconnaissance plane flying over islands in the South China Sea. The plane was repeatedly warned by Chinese military figures on the ground that it had entered Chinese airspace.

During the patrol, the P-8A Poseidon plane was repeatedly warned by Chinese callers that it illegally entered what they said was China’s territory and ordered the plane to move away.

“China has sovereignty over the Spratly islands, as well as surrounding maritime areas. Stay away immediately to avoid misjudgment,” one of the stern radio messages said in a veiled threat.

But the U.S. Navy plane dismissed the multiple warnings and pressed on defiantly with its reconnaissance in brief but tense moments witnessed by two AP journalists invited onboard. “I am a sovereign immune United States naval aircraft conducting lawful military activities beyond the national airspace of any coastal state,” a U.S. pilot radioed back to the Chinese.

“Exercising these rights is guaranteed by international law and I am operating with due regard to the rights and duties of all states,” he said.

The Navy plane flew over several islands which China started militarizing about a decade ago.

…some appeared to be like small cities on screen monitors, with multi-story buildings, warehouses, hangars, seaports, runways and white round structures Aquilino said were radars. Near Fiery Cross, more than 40 unspecified vessels could be seen apparently anchored.

The Chinese militarizing of three of the islands is now complete: Mischief Reef (pictured above), Subi Reef and Fiery Cross. Aquilino called it part of the largest military build up since WWII. China’s goal is to gradually lay claim more of the South China Sea as Chinese territory, hence the warnings that flights over the region have illegally entered Chinese territory. This map shows how far south Mischief Reef is of mainland China:

China has long claimed control of the majority of the South China Sea based on a 1947 map which established the so-called nine-dash line. That map, which originally had an 11-dash line,  was rejected as a legal basis for territorial claims in 2016:

First the dotted line on Chinese maps lost two of its hyphens in 1952, when, in a moment of socialist bonhomie with Vietnam, Chairman Mao Zedong abandoned Chinese claims to the Gulf of Tonkin. Then, on July 12, 2016, an international tribunal ruled that the now nine-dash demarcation could not be used by Beijing to make historic claims to the South China Sea, parts of which are claimed by six governments. The line, first inscribed on a Chinese map in 1947, had “no legal basis” for maritime claims, deemed the Permanent Court of Arbitration in the Hague. Beijing reacted with outrage to the judgment, which delegitimized China’s maritime ambitions according to international law.

On July 18, China’s naval chief Wu Shengli told the visiting U.S. chief of naval operations that Beijing would not halt its controversial campaign to turn the contested South China Sea reefs it controls into artificial islands complete with military-ready airstrips. China “will never give up halfway” on its island-building efforts, said Wu, according to Chinese state media…Far from hewing to the international court’s July 12 judgement on the nine-dash line, and contested features within that boundary, Beijing has made clear it considers the award null and void…

After the tribunal’s judgment was made, state media began a campaign to defend China’s maritime claims, encapsulated by the phrase “not one [dash] less.”

So this is Xi Jinping pressing for more territory despite the PRC’s claims being rejected by the rest of the world. Adm. Aquilino said it remains to be seen if China will continue trying to expand its territorial claims by building out other islands.