China's relations with Southeast Asian nations, which had warmed significantly in the mid-2000s, have since settled somewhere between cool and downright icy. While 2015 saw a thawing of relations, coastal Southeast Asian nations, like Vietnam and the Philippines, continued upgrading their navies and coast guards, building relations with the United States to hedge against Chinese power, and searching for novel strategies to constrain China's ambitions. At the same time, some mainland Southeast Asian nations, such as Laos and Thailand, not directly affected by regional maritime disputes, seemed increasingly comfortable with China's ascendance into a major Southeast Asian power.