After a brief stint as foreign minister which saw him alienating so many nations that Benjamin Netanyahu ended up running parallel diplomacy out of the prime minister's office, Avigdor Lieberman is back in the government, and this time as defense minister. While this has raised concern about what it does to Israel's diplomatic standing, it's not the big problem.
The real issue is that the occupied West Bank remains under Israeli military rule, which means that when he takes his new post, Lieberman, the pro-settler and anti-Arab ultra-hawk, becomes effectively the military ruler of the West Bank.
New bellicosity, new restrictions on the Palestinians, new crackdowns on the refugee camps, and accelerated settlement construction are all practically a given. New battles with the Israeli High Court and broader rules of engagement are certainly in the military's future.
Despite international criticism of Israeli military policy, particularly in the occupied territories, outgoing DM Moshe Ya'alon tended toward moderacy, and was constantly trying to de-escalate tensions in the West Bank, resisting calls from the rest of the government for even bloodier crackdowns.