Kublai's government faced financial difficulties after 1279. Wars and construction projects had drained the Mongol treasury. Efforts to raise and collect tax revenues were plagued by corruption and political scandals. Mishandled military expeditions followed the financial problems. Kublai's second invasion of Japan in 1281 failed because of an inauspicious typhoon. Kublai botched his campaigns against Annam, Champa, and Java, but won a Pyrrhic victory against Burma. The expeditions were hampered by disease, an inhospitable climate, and a tropical terrain unsuitable for the mounted warfare of the Mongols. The Trần dynasty which ruled Annam (Đại Việt) defeated the Mongols at the Battle of Bạch Đằng (1288). Annam, Burma, and Champa recognized Mongol hegemony and established tributary relations with the Yuan dynasty.