To see the effect of momentum at work, put yourself into the following situation:
The first light of dawn is barely showing over the distant Himalayas. You and a colleague arrive at the airport security access gate, driving a vehicle full of cargo. You’re a humanitarian logistician, responsible for flights that bring essential supplies to your post-earthqauke rehabilitation programs high in the remote montains. With the rainy season building, an early start is essential to complete the day’s flights before afternoon storms build up. It’s what you do at least three mornings a week.
A solitary soldier steps forward out of the darkness. You don’t recognise him.
“You can’t take that vehicle in,” he says, pointing to the access sticker on the windscreen. “That’s last year’s sticker.”
It’s March. Along with every other operator, you’re still waiting for the new year’s passes to be printed.
“You’re right,” you reply, “like you, we’re waiting for the new badges.” You indicate the man’s own security ID that hangs around his neck, which also shows last year’s date.
“Well, without a current pass, you can’t bring that vehicle in.”
The man blocking your way is brand new, part of the ever-shifting mix of soldiers, police, and friends of friends who have some murky, undefined level of authority at the regional airport.