BRUSSELS — The European Union, which does more than 1.5 billion euros a day in two-way trade with China, came late to the industrial, political and security threats China poses. For a long time, Europe saw China as another Japan, only with some human-rights issues.

But with the outspoken ambitions of the Chinese leader, Xi Jinping, and continuing battles over technology transfer, closed markets and industrial espionage, that is changing.

On Tuesday, the European Union and China met in Brussels for their 21st annual summit. The challenge for Europe is to forge a united front in the face of a China that only last month it labeled an “economic competitor” in critical industrial fields and a “systemic rival” politically.

The mood is certainly tougher now, especially after Italy last month became the first Group of 7 country to join China’s vast Belt and Road project, which the French analyst François Heisbourg described as “China’s own concept on how to organize the global space.”