An Iron Dome air defence system fires to intercept a rocket from Gaza Strip in Ashkelon.

An Iron Dome air defence system fires to intercept a rocket from Gaza Strip in Ashkelon.

If you’re  a British government politician who disapproves of Israel’s actions, you can register your opinions in various ways.

You can say so privately. This lets you tell it straight without anyone losing face. It’s what you’d expect friends to do, and what David Cameron likely did.

You can say so publicly. This is more risky. Criticism of Israel (as from Ed or Boris) plays well to a domestic audience but shows short-term thinking, because Israelis will remember it when you next need them.

You can resign in principle. This is riskier still. Doing so usually means you need others to do the same (as they did over Iraq a decade ago) lest it look personal, as it has done with the noble Baroness Warsi.

Or there’s the nuclear option.

An arms embargo – even an implied, limited, conditional, partial and/or pending one – has some advantages. It lets you distance yourself from the nastiness and it shows you’re actually doing something. You can see why MPs may like it.

Thereafter, though, the problems soon stack up, chief among them the uncomfortable reality that the UK has far more to lose in a defence industry trade war than Israel does.

When working out what to ban, you have to decide what constitutes a bad weapon, and when you ring-fence those worth lots of money (as the UK government did when excluding from review a £7.7 billion cryptographic equipment deal agreed with Israel last year to assist with its Iron Dome) you begin to look selective.

Among the remaining exports within firing range are those from 131 UK companies, including rifles, radars, tanks, engine parts, targeting systems and electronic warfare equipment. Most of this can be bought elsewhere.

That lot was worth just over £40 million over four years, which isn’t even small change when compared to £3.8billion in military exports to Saudi Arabia (not even our biggest export market) over the same period.

Pulling it would barely register. What would register is an Israeli response, not least because Israeli technology is central to a 25 year MoD contract worth £1 billion to develop Watchkeeper WK450 drones.

With so many reasons to avoid an arms exports war, we can only assume Cable and Clegg want to do so because they agree with groups like Campaign Against Arms Trade, which states: “An embargo would mean the UK no longer profits from the misery of Palestinians.”

But if the Lib Dems want their arms embargo to be a ban on nasty weapons to nasty states, they need to consider that the UK also exports weapons to such human rights darlings as Syria, Saudi Arabia and Sri Lanka, not to mention Iran, Belarus and Zimbabwe.

It seems curious that there is no similar media-inspired clamour to review these countries too.