In the US, the equilibrium between the three branches of government is guaranteed by a strict separation of powers. At any given point, control of the executive, the legislative (even the two chambers in the legislative) and the judicial branches can be split between the different political forces. Not only that, but the fact that the US Constitution is a law that can only be modified by a qualified super-majority also guarantees the stability of the legal principles that conform the Union.
Few of these protections are true in the Israeli system of government. To begin with, Israel has a parliamentary system in which, although there is a de jure separation between the legislative (the Knesset) and the executive, de facto, there is seldom disagreement between the two since the executive is elected by the legislative. In fact, most minister and other members of the executive are at the same time members of the Knesset. The Basic Law: The Government specifically requires that “The Prime Minister shall be a member of the Knesset.”
This brings us to the second major difference between the Israeli and American systems: The Basic Laws. Israel does not have a formal constitution. Instead, it has a set of “Basic Laws” that have something analogous to a constitutional status, except they do not require a qualified supermajority to be amended or modified. At any point, a simple majority of 61 of the 120 Knesset members can vote to radically alter the Basic Laws of the State of Israel, making them a much weaker protection for the rights of citizens, especially if they are minorities, than other modern Western constitutions.
That is something that the legendary Israeli Supreme Court President Aaron Barak recognized four decades ago, and the reason he fought for a strong Supreme Court that could override decisions of the Knesset and protect the rights of citizens even if they were not in the majority.
In order to guarantee the full independence of the Judiciary (remember, the only true “safeguard” in the Israeli system), all judges in Israel are appointed by a diverse selection comprising a total of nine members: The President of the Supreme Court and two additional Supreme Court judges, the Minister of Justice, an additional minister, two Knesset members, and two representatives elected by the Israeli Bar Association.
The current proposal for judicial reform being voted in the Knesset would change that composition and essentially give the government full control over the selection of judges in Israel. To many Americans, that would be familiar territory. But in Israel, it would grant the government absolute power over all three branches of government. Furthermore, the proposed reforms also remove from the court the possibility of judicial review of Knesset decisions that contradict Basic Laws. In other words, even if the court finds that a law passed by the Knesset is “unconstitutional,” the Knesset could override the decision by a simple majority (which the ruling coalition is assured to have).
That is the reason why hundreds of thousands of Israelis are taking to the streets to protest the reforms. They understand that approving the current reforms is much more than simply fixing a system that, like any other, can certainly use modifications, but in fact, is a real and present threat to the democratic character of the state.