Any food can make you fat if consumed in excess, in the presence of insulin.
Because in order to store the food's energy as bodily fat, it needs insulin to get the energy into the cells.
Fat consumption hardly stimulates any insulin release, protein consumption doesn't stimulate much insulin release (unless eaten in excess), carb consumption stimulates lots of insulin.
So if carbs are eaten, more insulin is required, and it is easier for any excess energy to be stored.
Shall we all sing, in chorus:

Not all calories are created equal
