Is your trip really necessary, Prime Minister?

Should John Key press ahead with his scheduled visit to Europe - a trip most notable for him and his wife, Bronagh, being invited by the Queen to spend the weekend with her at Balmoral Castle, the royal residence in Scotland?

Or should he cancel the trip - he is due to fly out on Friday - and stay home as a gesture to the people of Christchurch as they pick up the pieces of their lives after Saturday's earthquake?

Had the quake caused fatalities, it would an easy decision to make.

That there were no fatalities does not disguise the obvious fact that New Zealand's second-largest city is reeling.

As Key himself has noted, many people are suffering varying degrees of mental trauma and shock.

Even for those who are not, the grim reality of weeks, if not months, of disruption is sinking in.

About 100,000 homes out of 160,000 in the Christchurch area have suffered some kind of damage. That is a mammoth number. Community spirit can only go so far before it gives way to frustration, anger, despair and depression.

When such feelings could potentially run wild, it is not the time for a leader to be seen to be half a world away in another world sipping the finest-blended tea out of the finest bone china on the finest-cut lawns, with the biggest annoyance being the corgis snapping at your heels.

As the Prime Minister also stressed yesterday, the business of government has to go on.

Apart from Balmoral, Key's visit to Britain will present his first chance to talk at length with David Cameron since he became prime minister after Britain's election in May.

He is also going to Paris for meetings with President Nicolas Sarkozy and Prime Minister Francois Fillon.

But none of these discussions are in the "must-happen" category.

There are no issues in New Zealand's relations with either Britain or France which are so pressing they could not be postponed until another occasion. Likewise, the side-trip to Scotland.

One event on Key's itinerary does justify his presence in London. That is the unveiling of a statue in memory of Air Chief Marshal Sir Keith Park in London.

It is particularly poignant that the unveiling of the memorial to the New Zealander who led Fighter Command during the Battle of Britain should be occurring on the 70th anniversary of what was one of the crucial battles of World War II.

But even that pales in comparison to the here-and-now of Christchurch. No one needs to tell Key of the political risks. He has sought to forestall criticism by ensuring before he leaves that everything has been put in place to begin the massive reconstruction effort needed in coming months. He has appointed a Minister for Earthquake Recovery. He will spend part of today and tomorrow in Christchurch and surrounding areas.

Key is trying to make himself surplus to requirements. On that basis, logic would suggest he go if he can achieve little by staying at home.

But logic is not the only factor in play. Feelings and emotions are as well. The Government's response to the earthquake has been nigh-on faultless. But it would not take much for that perception to change.

At this stage, he says, he is going. But he will wait until the last minute before making a definitive decision. That he is doing so may tell him that - on balance - he would be wiser to stay put.