The United States did not directly mention China in announcing its historic new security partnership with Australia and Britain last week, but it didn’t have to. The defense deal is a clear escalation and indication that Washington views Beijing as an adversary. It also has thrust Australia into a central role in America’s rivalry with China. After hinting at a more self-reliant defense posture for the past several years, Australia’s government is now instead betting big on the future of its alliance with the United States with the new pact.…