THERE has been barely a peep of protest from Conservative MPs since the axe was swung on Government spending almost five years ago – until now.

Local councils warning of disintegrating services have been urged to cut waste and streamline, while benefit claimants are told it will cure their “welfare dependency”.

Even dramatic cuts to police budgets – which might be expected to trigger a Tory backlash – have been swallowed, dissent neutered by the continuing fall in crime.

But now, with this parliament’s finishing post in sight, a revolt will be staged today, as the spending cuts finally go too far for many Conservatives.

The issue? Defence – and the sudden realisation that David Cameron is backsliding on a commitment that for so long seemed sacrosanct.

Only last September, the prime minister, speaking to the Nato summit, urged all countries to sign up to a target of spending two per cent of their GDP on their armed forces.

And he told his fellow leaders: “We must increase our capacity. This would send a strong message to those who threaten us, that our collective resolve is as strong as ever.”

Well, now another leader is on course to miss that target and his name is Cameron – and that failure is likely to be set in stone within weeks.

The two per cent pledge is expected to be missing from the Conservative manifesto, with the Ministry of Defence tipped to receive only a “flat cash” settlement if the Tories win.

That would see defence spending slipping to just 1.7 per cent of GDP by the end of the decade - below the level of Nato allies such as Poland and Romania.

And, today, up to 30 Conservative MPs will awaken from their slumber about cuts, staging a Commons vote to demand the two per cent target is reinstated.

They will be buoyed by a Royal United Services Institute (Rusi) warning that the army could shrink to only 50,000 soldiers, with key equipment programmes - from fast jets to Navy frigates - under threat.

Now, I’m sure Tory MPs will make a convincing case for higher defence spending today – a fairly easy task when the Russian bear, under its Cold War-loving leader Vladimir Putin, is roaring anew.

But will they make the connection between the shrinking defence pot and the eye-popping spending plans announced by George Osborne, for post-2015?

After all, do we think the prime minister no longer cares about defence, that he gets out of bed determined to sack soldiers and to give himself internal party grief?

Or is it more likely that he has boxed himself in by what the independent Institute for Fiscal Studies calls “colossal” future annual cuts of at least £50bn, planned by his Chancellor?

Today, Conservatives will line up to moan the defence of the realm would be secure if only their party wasn’t planning to blow billions on overseas aid and high-speed rail.

But the reason the two per cent pledge looks doomed is that the Conservatives – with NHS spending to be ring-fenced again - simply cannot protect the MoD as well and make those cuts.

If will be nice if that reality is acknowledged during today’s debate.