After months of chest-thumping, accusations and threats, look for US-China trade relations to weather an uneasy pause as the giants retreat from extremist positions, guard against backtracking and alter the negotiating dynamic toward an eventual agreement, analysts and former US officials say.The breather follows this month’s London sit-down after the two engaged in a high-stakes tariff battle then went for each other’s jugulars, with China blocking rare earth exports and Washington choking off...