Government, councils and the emergency services rehearse for it regularly.
But when a tragedy the scale of Grenfell Tower strikes, desktop exercises become desperately real situations.
Some emerge with credit, others less so.
Watching the TV news at home, I witnessed London’s mayor Sadiq Khan walk through the crowds near the stricken tower.
He was there to meet residents then talk to the media.
He did so as residents came to terms with the loss of family, friends and homes.
For others, faint hopes of finding loved ones alive were being extinguished with the still-burning embers of the fire.
So it was inevitable that the mayor would meet grief, shock, anger, resentment and hostility among many other emotions in that community.
He walked solemnly, speaking to people along the way.
Occasionally an insult would be thrown – which he’d ignore.
When he started to address the media, some heckling broke out.
He would stop if it came in the form of a question, answer the question and return to his point.
It’s impossible to know in these situations which members of the crowd were actually affected by the fire.
Some had only come along to make a political point.
Khan treated the hostility with calm.
His calm exterior caused others in the crowd to spring to his defence, telling one heckler to shut up.
A Sky News presenter stated that Mr Khan had offered himself up “as a lightning conductor”.
There to absorb the shock and anger in the air.
I believe it’s the duty of politicians and council leaders to do what the mayor did.
They should stand up and face the music in the wake of such a tragedy.
But his visit only served to emphasise how Prime Minister Theresa May handled the same situation.
Downing Street was slow to issue a statement in the hours after the fire.
When the PM went to the area, it was to visit the emergency services who had fought so hard to save lives.
She then went to a hospital to visit the injured.
Eventually, community leaders were invited to Downing St. to express their feelings.
Now during a crisis, it is absolutely right to hold those meetings and conduct those visits as part of your communication plan.
But what was missing was the Sadiq Khan approach and his empathy.
During a crisis, leaders need to stand up to be counted.
They need to face their critics, speak compassionately and with purpose.
Mr Khan did all of that through his communication.
But a number of others have trotted out bland lines about “lessons must be learned” in that passive, disinterested-sounding way.
That seemed inappropriate while a recovery operation was still underway.
Our advice to those facing such difficult circumstances is this:
In that respect, Sadiq Khan made a dreadful situation slightly better by his proactive approach.
Bill McFarlan is Executive Chairman of Pink Elephant Communications in Glasgow.
You can view his full profile here…
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