Like those from a battering ram, the hits just keep coming from the recently elected president of the Philippines, Rodrigo Duterte.
Saying this week that President Obama could "go to hell," Duterte has threatened to jettison decades of close security cooperation with the United States, suggesting Manila would turn to China or Russia for support.
The latest anti-U.S. vitriol came as U.S. Marines and sailors practiced amphibious landings and other exercises with Philippine troops at coastal sites close to the strategic shipping lanes and disputed islands in the South China Sea, a regional hot spot.
The joint exercises began Tuesday and are scheduled to run until Oct. 12. Last week, Duterte said this would be the final round of joint exercises with the U.S. military.
Obama administration officials have chosen to largely ignore Duterte's insults and ultimatums, and say they have not scaled back any military or aid programs in the Philippines.
"The administration is playing this as well as one can," said Amy Searight, director of the Southeast Asia Program for the nonpartisan Center for Strategic and International Studies in Washington. "The best option for the U.S. is to stay calm and let it play out. We don't know yet where Duterte plans to go with this."
Washington and Manila have had a mutual defense treaty since 1951 and Defense Secretary Ashton Carter said that military partnership remains "ironclad."
He spoke in Honolulu after meeting with his Philippine counterpart, Delfin Lorenzana, at a weekend gathering of defense ministers from the Assn. of Southeast Asian Nations, a regional grouping that promotes economic, political and security cooperation.
Lorenzana said Wednesday that Duterte might be "misinformed" about the value of the Philippines' military cooperation with the United States
Josh Earnest, the White House press secretary, said Tuesday that Duterte's harsh comments are "at odds with the warm relationship that exists between the Filipino and American people."
Last month, Duterte used a common slur in Tagalog that roughly translates as "son of a bitch" to refer to Obama. The White House responded by canceling a planned bilateral meeting on the sidelines of a regional summit in Laos.
Duterte later said in a statement through his spokesman that he regretted that his language "came across as a personal attack on the U.S. president."
White House officials had said Obama was concerned about widespread extrajudicial killings since Duterte was elected on a vow to declare war on illegal drugs. Police and vigilantes have killed more than 3,500 people since Duterte took office June 30.
"Words do matter," a senior State Department official said, requesting anonymity to speak candidly. But, the official added, "we are not going to respond to every little thing said in Tagalog somewhere in the Philippines."
The Philippines spent five decades as an American colony until it won independence after World War II, and relations have been stormy numerous times in the past. In 1991, the U.S. was forced to give up major air and naval bases in the country.
Obama has visited the Philippines twice in the last four years in an effort to broaden ties. It paid off with wider U.S. military access to Philippine bases and ports, and greater cooperation on counter-terrorism programs.
In 2014, Washington and Manila signed an enhanced defense cooperation agreement partly in an effort to provide a stronger counterbalance to China's expansion in the resource-rich South China Sea, where it is building artificial islands.
The agreement, now criticized by Duterte, was upheld as constitutional by the Philippine Supreme Court on Jan. 12.
The Pentagon keeps 300 to 500 troops in the Philippines to support training, joint exercises and other activities. About 50 to 100 members of the U.S. special forces also work with Philippine security forces, especially in the restive southern islands.
Cmdr. Gary Ross, a Pentagon spokesman, said the U.S. military has been consulting with Manila over the last two months "on ways we can support the new administration's counter-terrorism efforts."
Ten weeks ago, the Philippines won an important legal victory when an international tribunal, the Permanent Court of Arbitration in The Hague, ruled that China's "historic" claims to islands and reefs in the South China Sea were invalid.
Duterte, however, has sought to move closer to Beijing, which is a major trading partner for Manila.
"There is a history of anti-American sentiment that gathers around sovereignty issues [in the Philippines] and Duterte can tap into that," said Sheila Smith, a senior fellow at the nonpartisan Council on Foreign Relations in Washington. "But he is playing rather dangerously, thinking 'we can cozy up to China' … as a hedge."
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