“If we’re not at the table, we’re on the menu,” was Mark Carney’s warning to fellow “middle powers” earlier this year. Looking at this week’s US-China summit, the European Union will know exactly what the Canadian leader was getting at. As Donald Trump and Xi Jinping prepare to discuss artificial intelligence, trade and global instability, Europe is being reminded once again of its relegation to bystander status after years of punching below its weight in defense and technology.