If all governments could be trusted, no-one would ever need a supreme court.

Britain being Britain, we get a compromise and a paradox, a body you could define as "almost supreme". Scotland complicates matters, for one thing, by maintaining its supremacy in criminal matters. But the Supreme Court of the United Kingdom is better than nothing, just about.

It showed as much last week by ruling that the families of some of those killed in Iraq have the right to bring compensation claims against the Ministry of Defence. The grounds, predictably, are negligence and human rights. No sanctions against the ministers, civil servants and officers who kept the bereaved waiting a decade for their chance of justice were mentioned, but it was ever thus.

British military history is littered with the tales of ill-equipped soldiers being sent off to fight stupid wars by people who rarely, if ever, face the consequences. In Iraq and in Afghanistan the miserable tradition has been maintained. While Tony Blair and his friends were spinning the country a line about dictators and destructive weapons, it was almost easier to ask which pieces of British kit were up to the job in Iraq than to note the failures.

You might remember the rifles that fell apart, or the boots with the melting soles, or the communications systems that failed to communicate. You might recall the absurd but perfectly true tales of troops buying their own gear, body armour above all, because the MoD didn't have enough to go around.

The scandal of the Snatch Land Rovers was perhaps the worst of them all. By rights, it should have led to something more serious than compensation claims, but that's not the British way. First, deny there is a problem. Then persist with the folly to the point of madness. Then ignore the grief and outrage for years. Then employ every legal means to delay any sort of reckoning.

Veterans who chat online remember those Land Rovers. As one put it last week, they had flooring "you could open with a tin opener". Perfectly good working vehicles outside a war zone, they were death traps when set among mines and other explosive devices. The nickname "mobile coffins" was only half a blackly comic joke.

Lower courts had entertained the idea that claims of official negligence by the families could be allowed over this issue, but rejected the suggestion – I paraphrase slightly – that soldiers can have human rights. The Supreme Court picked apart the arguments.

One had to do with a so-called "covenant" by which the MoD is absolved of a duty of care when the shooting starts. Another involved UK "jurisdiction" in a war zone and the ensuing obligation under the European Convention to protect the human right to life. A third had to do with the official duty, if any, to the dead. Behind it all lay a simple accusation. Soldiers were ordered out on patrol in those vehicles time and again in Iraq and Afghanistan when the MoD knew perfectly well – for casualty lists don't lie – that the Land Rovers offered no protection against roadside bombs. In both conflicts, dozens perished as a result. It was, in tabloid language, the health and safety argument to end them all.

Our politicians are fond of honouring the fallen when all that's asked is a solemn moment at the Cenotaph, or a speech to justify army redundancies. The same ministers have sanctioned a decade's worth of delaying tactics against the families who took their case to the Supreme Court.

"Compensation" is hardly the word for what ought to be punitive damages. If that happens, well and good, but it will not resolve a fundamental problem.

Philip Hammond, the Defence Secretary, was one of those who backed the preposterous argument that those fighting, killing and dying on Britain's behalf are somehow beyond the country's jurisdiction. He also advanced the curious claim that the MoD had responded to the Land Rover problem since the litigation began by introducing vehicles with daft names – the Mastiff, Ridgeback, Husky, Wolfhound, Jackal and Foxhound – to improve protection. Hammond was boasting, in effect, of having done too little too late.

You can also set aside his specious claim that "national security" could be jeopardised by the ruling. But you cannot resolve a basic difficulty when human rights law and the business of war are set in opposition. Those who died in the Snatch Land Rovers were given no protection: that much is plain. How much protection is enough? The new vehicles mentioned by Hammond are better than the old vehicles, but they still get blown up. As armour is added, the bombs get bigger.

There is, equally, the noble aspiration of the European Convention to create a duty to "protect the right to life". Can that ever be applied, honestly and consistently, to killing fields? If a soldier dies in a "friendly fire incident", as happened to Debi Allbutt's husband, Stephen, a claim of negligence surely must be heard. But where does the duty of care end in a war zone?

Early last year, General Sir Peter Wall, Chief of the General Staff, gave a speech ruminating on what he took to be the growing belief that in "properly equipped" wars no-one should be killed. "I sense there is an expectation in some circles in society," Wall said, "that the sort of zero-risk culture that is understandably sought in many other walks of life ought to be achievable on the battlefield."

One response might be that the general and the rest of the officer class should stop assuring politicians and the public that the armed forces will always "get the job done", no matter what. Iraq and Afghanistan have shown that such promises are kept at an obscene cost. Set aside our unusable nuclear weapons and Britain is, at best, a middle-ranking European military power notorious for its "equipment failures".

Wall had a point, nevertheless. If someone can sue because the vehicles offered to troops were pathetic tin cans, why should there be no right to sue because an officer gave foolish orders, because a politician set ridiculous objectives, or because the war was illegal to begin with? One question leads to another. What does a young person expect when he or she signs up? The best kit available – a sound demand – or kit that is somehow perfect for all conceivable occasions?

In wars, people kill and die. Soldiers are trained, we hope, to understand that reality. Sending them out with what one lawyer last week called "a broomstick" is unacceptable. Sending them out as though they have no human rights makes a mockery of the values we are supposed to be defending. But putting troops into combat with the expectation that a government has a duty to "protect their right to life" is nonsensical.

There is only one way to protect that paramount right. When a society that claims to be a democracy acquires the will and the means to prevent its leaders from launching meaningless proxy wars, the chances for injustice are reduced. That doesn't mean an end to conflict forever more, however. Those who sign up should always know as much. They should certainly be told the truth.