One hundred days ago, David Cameron and Nick Clegg turned and waved as they entered the front door of 10 Downing Street. Several people observed that they looked a bit like Morecambe & Wise at the end of their TV show, writes John Hipwood.

But the last three months has been anything but a barrel of laughs. Instead of bringing us sunshine, the Conservative-LibDem coalition Government has brought us gloom. And it has been quite deliberate.

Double, double, toil and trouble; fire burn and cauldron bubble. Like the three witches in Shakespeare’s Macbeth, Cameron, Clegg and George Osborne have been stirring up an austerity potion which will affect every person in the land – and some a great deal more than others.

Nothing short of malicious vandalism, according to Labour veteran Tony Benn.

It all started so brightly with that press conference in the Rose Garden in Downing Street. The Prime Minister and his Lib Dem deputy, who had been slagging off each other’s policies in the run-up to the May 7 election, laughing and joking together like bosom buddies. The Brokeback Coalition.

I watched them in amazement as journalist colleagues turned to each other and asked: “Is this real? Can it possibly last?”

Well no, of course it couldn’t last. As the cuts began and the Coalition policies emerged, the tensions grew. But the happy couple are still hanging on in there, in the certain knowledge that if the partnership falls apart, the Government could fall and the Liberal Democrats could be wiped out at an emergency election.

Despite the tensions and inevitable emergence of Mr Cameron as the dominant partner, the pace of the change brought about by the Coalition has been staggering.

Mr Osborne’s emergency Budget was all about cutting the huge national debt with a combination of tax increases and spending cuts. The impact of the VAT increase to 20 per cent won’t be felt until the new year, but ministers were told to consider departmental cuts of up to 40 per cent.

We still don’t know precisely what the cuts will mean. We will have to wait until October for that, but an indication of what’s to come came last week (not much rest for ministers, even in August) when Defence Secretary Liam Fox indicated that thousands of civilian jobs in the Ministry of Defence are to go.

This at a time when Britain’s commitment in Afghanistan is as great as ever, notwithstanding Mr Cameron’s signal than he wants our troops out by 2014.

Communities Secretary Eric Pickles waved goodbye last week to the Audit Commission, the quango which monitors the spending of local councils. Checks on town hall spending will have to continue, of course. Will the private sector be able to do the job more efficiently and cheaply? Mr Pickles certainly thinks so.

Elsewhere, we have had proposals for another major change in the way the National Health Service is run, with much greater responsibility for GP practices; while Education Secretary Michael Gove, who found himself in all sorts of trouble over the scrapping of the Building Schools for the Future programme, pressed on with plans to allow all schools to be become academies.

Many Shropshire students will, tomorrow morning, receive their A-level results, but a significant minority will not be offered the university places their achievements would normally guarantee them.

Home Secretary Theresa May hasn’t been idle in a cabinet role which frequently destroys political careers. She reacted with common sense to the Cumbria murder spree, scrapped identity cards and signalled the end for anti-social behaviour orders.

Justice Secretary Kenneth Clarke, a man who can be relied on to speak his mind, caused controversy and some consternation in police and Tory circles by voicing his opposition to short prison sentences.

Business Secretary Vince Cable did his best to emasculate regional development authorities, and his Liberal Democrat colleague Chris Huhne announced a mish-mash of an energy policy, which seems to include nuclear (but not subsidised by the taxpayer) and definitely includes destroying our land and seascapes with more white elephants called wind farms.

On an individual basis, Mr Clegg has been a robust and combative performer in the House of Commons, causing a bit of stir at No 10 when he branded the Iraq War “illegal”. His plan to hold a referendum on changing the Westminster voting system on the same day in May as the elections for the devolved administrations has also caused consternation in Conservative ranks.

The Deputy Prime Minister has, however, been almost completely overshadowed by Mr Cameron, who has shown incredible energy and a decisive command of the Commons despatch box. Our democracy desperately needs an effective Leader of the Opposition to give him a true test.

The Prime Minister has conducted an interesting form of diplomacy, voicing opinions without apparent concern about upsetting other leaders, as we saw with his comments about Pakistan “looking both ways” in relation to terrorism. He even managed to anger people at home by labelling Britain as junior partner to the USA in 1940 when we were standing alone against Nazi Germany.

Mr Cameron also caused concern in this country by failing to respond swiftly enough to the anti-British sentiment in America caused by the oil spill in the Gulf of Mexico. He was among the few who failed to spot the hypocrisy and double standards of a nation which never accepted responsibility for the Bhopal disaster.

While the Tory leader’s personal rating remains relatively high, the latest opinion reported that when people were asked the Morecambe & Wise question ‘What do you think of it so far?’, 57 per cent thought that the Coalition has been disappointing.

By contrast, 56 per cent of people think that “deep cuts” are essential, with only 25 per cent opposed. The first figure is certain to fall and the latter rise as mums, dads, sons, daughters and friends see their wages fall or lose their jobs.

If the first 100 days were tough, the next 100 will be harder as inflation rises, and even those who do have savings see their standard of living fall.

Politically, the signs are not good for the Coalition. The Tories are down seven per cent in the opinion polls since the election, and Lib Dem support has halved to just 12 per cent. A rudderless Labour Party has dropped just one point to 28, and ought to gain popularity when its new leader is elected next month.

When the going gets tough, the tough get going. We have yet to see how tough Messrs Cameron & Clegg, and those around them, really are.