more of a danger（为什么要加of）

2 more of a danger（为什么要加of）

German's post-war pacifism was once comforting to its neighbours and to Germans themselves. Yet, with the passing of the generations, attitudes have shifted. Sensible Europeans long ago stopped seeing Germany as a threat. On the contrary, the passivity of its foreign policy has in recent years posed more of a danger, by encouraging aggressors such as Vladimir Putin. At last Mr Putin’s unprovoked invasion of Ukraine has convinced Germans to take security seriously. As Olaf Scholz's first budget makes clear, Germany is preparing to pull its weight. The task for Germany’s new chancellor is to make sure that the effort is sustained, effective and encompasses risk-sharing as well as just cash-splurging.

怎么理解这里的more of a danger，为什么要加of，more danger不就可以了嘛？