Let's go straight to the point: barbed wire. Have you ever snagged yourself, torn your clothes or even drawn blood on the stuff?
Probably you have. So have I – all three in fact.
One of the people we have to thank is Mr Lucien B Smith of Ohio.
He took out the first patent for the invention in 1874.
There have been many versions since, and there are at least two museums in America entirely devoted to it, with more than 2,000 variations in its design.
Its purpose, of course, was to enclose cattle on the open prairie, and being much cheaper than the alternatives was possibly as significant a factor in the settlement of the Wild West as the horse and the railway.
Mr Smith's lucrative idea became an industry, which expanded rapidly, and must have made a killing, so to speak, in World War 1.
It probably arrived in the Lake District about the same time, and now there is scarcely an acre of our national park that isn't positively garlanded with the stuff.
This was true of one hill in particular in the north of the county that was my objective a few weeks ago.
Like most fell-walkers with a total knee replacement and a dodgy hip I look for routes that ascend steeply and go down gently.
I found one, marked on the map, signposted through a wood and obviously recently used.
After two hundred yards I came across the first fence: four feet high, no stile and topped, of course, with barbed wire.
As my predecessors clearly had, I climbed over it and carried on.
Another hundred yards up the track, and just where the trees gave way to open country – another barbarous fence! And this time a pair of torn trousers.
I suppose these fences had some spurious connection with sheep (since the foot and mouth outbreak of 2001 they seem to have sprung up everywhere) but why the barbed wire?
There will never be cows on this hillside, and the sheep aren't going to take up high jumping in order to impale themselves on it.
And sure as hell it isn't going to stop fellwalkers like me from going where we have a right to roam.
All it can do is punish us for trying. In which case it is possibly, in legal terms, an 'offensive weapon', and its installation at least could be described as 'threatening behaviour'.
One winter, years ago, I angered my son when I wouldn't let him use a snow-covered track on which other children were tobogganing.
We later learned that a boy had been injured there – fortunately not seriously – by barbed wire, not on top of the nearby fence, but about two feet above the ground, or eye level when you're sitting on a toboggan.
How many accidents like that happen each winter?
Which still leaves the question: why barbed wire?
Most of it is where no cows roam, sheep are rarely contained by it, and fellwalkers don't go around climbing over fences and dry-stone walls just for fun.
I suspect that it's not much more than a habit: there's the fence, here's the barbed wire – we simply take it for granted. We shouldn't.
All of which may be disputed. But what cannot be denied is that barbed wire is ugly; its baleful presence in a beautiful region like ours is jarring and discordant.
On aesthetic grounds alone we should eliminate it from the landscape.
Or must we start to include a pair of wire cutters in our equipment when we head off into the hills?