Like “military music” and “military intelligence”, “military justice” is a concept that can often seem to be a contradiction in terms.

So it seemed to many on Tuesday morning as the IDF military court sentenced Sergeant Elor Azaria to 18 months’ imprisonment and a demotion to the rank of private for the manslaughter of Abdel Fattah a-Sharif last year in Hebron.

After the same court’s damning verdict two months ago, which found Azaria guilty and took to pieces the case for the defence, a much stiffer sentence seemed likely to many.

To many critics of Israel’s policies towards the Palestinians in the West Bank, this is simply further proof that Palestinian life is cheap.

There is some truth in this, but things are never that simple in a court room where the judges and the accused are wearing the same uniform and the court has a duty not only to uncover the truth and punish the guilty, but also to safeguard national security as they see it.

The expectation that Azaria would receive a sentence similar to that of a civilian convicted of manslaughter in a regular court was never realistic.

Not only because of the victim was a Palestinian who, minutes earlier, had tried to stab another soldier and was already mortally wounded.

In the small number of countries where soldiers can be court-martialed for misconduct on the battlefield — or where police are put on trial for brutality towards civilians — the fact that soldiers are given a weapon and sent on a mission by the government is almost always an extenuating circumstance and the sentence routinely reduced.

Even so, 18 months does seem very short, even for a military court.

The Hebron shooting case was not really about Elor Azaria or Abdel Fattah a-Sharif. The judges had a duty towards the IDF, and the Israeli public, to make it clear that shooting a incapacitated assailant who no longer posed a threat was not just an operational misdemeanour, but a morally reprehensible, criminal act. They did that with a lengthy and unequivocal sentence. Two months later, they preferred a short, custodial sentence in the hope that the message of the verdict would allow both the IDF and Israeli society to achieve closure and move on.

If the initial reactions in the courtroom and in the country are anything to go by, they seem to have failed.

Azaria has refused to admit any guilt and is still surrounded by supportive family and admirers. According to one flash poll, a majority of Israelis support pardoning him, including many ministers. The public’s attitude may change over time, but if the judges thought a relatively lenient sentence would shut the door on this case, they were wrong.