China and the United States have sailed aircraft carriers into contentious waters in the East and South China seas, the latest maritime contest between the strategic rivals at a time of heightened tensions in the region. Analysts say their naval presence in the Indo-Pacific at the same time highlights the risk of military conflict between the powers, as Beijing asserts its maritime claims in the region more aggressively and Washington focuses its defence strategy on countering China. It comes amid a deepening dispute between Beijing and Manila over the presence of Chinese vessels - which the Philippines says are a...