LONDON — While much of the hand wringing over China has abated somewhat during the Covid-19 crisis, the fears animating Western attitudes toward that country have not disappeared, and could resurface at any moment. These tensions represent a major, vexing dilemma for the world, given China’s massive and growing economic power. And the situation certainly hasn’t been helped by the failure of the other major economic powerhouse, the United States, to manage the current crisis effectively. Owing to my professional background, I usually approach issues like the Sino-American relationship first as a macroeconomist. But as the chair of Chatham House, I have been developing a more nuanced view of the issue, taking into account not just the economic dimension but also security, diplomacy, culture, and other factors. To that end, it seems only reasonable that we should adopt a broader “optimization framework” for understanding and managing relations between China and the West.