If you ever wonder why so many Americans have so much trouble making their government function, just watch them making a shambles of another shared space — the infinitely simpler bike path.

I nearly got crashed twice yesterday — first by a pair of knucklehead roadies in team kit who cut across my bow in Goose Gossage Park, exiting the bike path for the street without bothering to check for oncoming traffic, and a few minutes later by some helmetless dipshit on a beater road bike careening down the wrong side of a sketchy slope coated with sand and pea gravel.

Mind you, these incidents constituted the cherries atop a turd-cake that included the usual ingredients — oblivious strollers three abreast, untrained dogs sans leash, and fleawits wandering across the path without checking to see whether they might be about to violate the laws of physics by trying to occupy the same space at the same time as a 180-pound Irish-American on a 30-pound touring bike traveling at 15 mph.

The offenders invariably wear the blank, bovine gaze of a feedlot cow doomed to wear a soggy bun, a slice of pickle and some processed cheese “food” in the afterlife. And yet some of us we marvel at the popularity of Rupert Murdoch’s various entertainment outlets, which shove a similarly toxic product at the feeble-minded through the flat-panel windows in their living rooms.

How hard can it be to walk, run and ride to the right, pass left, and keep your fucking eyes open?