For decades, the United States was seen as the world's most influential power: its word carrying weight from Washington to the most distant capitals. But that assumption is now being tested. A new global survey has found that China is viewed more favourably than the US in most countries surveyed, the first such reversal in nearly two decades. Is this China's diplomatic triumph, or America's soft power problem? This week's Faultlines breaks down what's driving this dramatic shift in global opinion.