Philippine election could cause heartburn for its US ally

The winner of Monday's vote will be hand-maiden to the most crucial U.S. relationship in Southeast Asia, and the front-runner has not inspired confidence with his casual threats to shoot criminals and by joking about the gang rape and killing of a foreign missionary.

[...] they'll be hoping for a successor who will follow the strategic path forged by Aquino, who has doubled down on ties with Washington in the face of China's aggressive pursuit of territorial claims in the disputed South China Sea.

On Aquino's watch, the Philippines has agreed to opening up several of its military facilities in American forces — a quarter-century after nationalist sentiments forced the closure of U.S. bases in the island nation.

"The Philippines has adopted an adversarial posture with regard to China that is unique in the region," said Marvin Ott, a former U.S. intelligence analyst and now a lecturer on Southeast Asian studies.

Vikram Singh, a former senior U.S. defense official, said it was possible that as president, any of the candidates could slow the recent agreements on increased U.S. military access to Philippine bases, but he expected "they'll want to keep close ties with Washington when they see just how significant the pressure can be from Beijing."