Netanyahu is, in fact, desperate to add another party to the coalition because there is so much tension in the current majority, most visibly between Netanyahu’s Likud party and Naftali Bennett’s HaBayit HaYehudi. Likud leaders, including Netanyahu, feel that Bennett essentially held the coalition hostage to his demands. They are quite right about that, but the gambit paid off handsomely for Bennett.
HaBayit HaYehudi holds a mere eight seats in the Knesset. Yet Bennett and his party will get four ministries, the deputy defense minister post, as well as the chairs of two key Knesset committees dealing with Israel’s legal system. That is what you get when you play hardball with Netanyahu, a man who likes to talk tough but who is a political creature first and foremost and quickly backs off from a high-stakes fight he is not sure he can win.
As things stand, this coalition might not last the year. That is why, after Avigdor Lieberman quit his post as foreign minister and took his greatly diminished party into the opposition, Netanyahu left the post open by keeping that portfolio for himself. In reality, Netanyahu has been the foreign minister all along, so it is not an added burden for him.