That's what I would do in his position. Go to Gaza and demand to see his son. Hamas would do no harm to him, because the publicity would be terrible for them if they did. The move would publicise his son's plight, but it would also let him build bridges with the suffering of Gazans. It might or might not help get his son released, but it would achieve far more than now. Does he seriously think that speaking out against the relaxation of the siege will help get his son released?
Ofir Akunis officially replaces Danny Danon as minister of science, technology, and space (Haaretz)
from the article: Noam Shalit slams Netanyahu over ease of Gaza blockade