to close HK US consulate without escalating the tension later on.

The US embassies/consulates have shown in the past they have no interest in obeying international conventions,  incited violence and sponsored color revolutions. It has already done so in Hong Kong by meeting the leaders of the riots in hotels and it will do so again in the future. When it happens again, what should China do? Close the consulate, expel the staff involved or like what China did the last time around expose the details and the personal information of the consulate staff involved? By then, the US can turn around and accuse China of inflaming the conflict, acting aggressively, and ratcheting up the tension. Why give them an opening at all when they give you the excuse to cut off the head of the snake.