phoning the goverment?

I wanted to call Secretary Kerry's office somehow, to be supportive of his speech criticizing Israeli settlements in the West Bank. I can't find a phone number on the State Department web page. I had the passing thought of writing a note and sliding it under the door at his home on Louisburg Square in Boston, but I suspect there is some security presence that might wrestle me to the ground, or worse. Also, one would hope they have good weather strips on the door.