>>1056786Some place like to fence the railroad tracks, especially around urban areas. Here in Spain tracks within urban and metro areas usually have some sort of fence, though it's usually some shitty little fence mostly to keep retards from accidentally walking onto the track.
What is more common than track damage is the communication cables being stolen. This has at times left significant stretches of track out of service because the cables had been stolen.
Some more daring robbers try to steal the overhead wire. This also leaves the track somewhat useless if the railway is highly dependent on electric traction.
I don't know how many missing sleepers are a problem, but certainly missing the occasional one is no big deal. I've see trains passing trackwork where there were fewer sleepers than is usual and there was no problem. I guess you'd need to remove/break quite a few before the rails lose stability and the train derails.
I guess they don't worry much about people damaging the tracks, at least here, because there's little point other than terrorism in damaging tracks, and it's really hard to do so in the short span of time between service ending and starting again (add to that the danger of trains during the night, like freight and sheit). Also trains are no longer as essential as they were in the past.
In past times, it was not uncommon to sabotage rail tracks. A relatively small explosion can damage the tracks enough to make them unpassable.