Sure, but there is some hypocrisy going on. They were created "to conserve the scenery and the natural and historic objects and wildlife therein, and to provide for the enjoyment of the same in such manner and by such means as will leave them unimpaired for the enjoyment of future generations."
I think the jumpers are not impairing them for future generations, but some others are.
More than 60 people have died on Half Dome and very few of them are BASE jumpers. The cable path up there doesn't seem to "maximise preservation".
An note about the cables, mostly because I've always found this to be a weird historical aside.
The cables today were put up in 1919, but follow closely both the style and path of the first ascent of Half Dome, which took place in 1875, 15 years _before_ Yosemite became a National Park. The first ascentionist basically drilled a bunch of holes up the side of the dome and used sticks or poles or something stuck in them to pull his way up like a ladder. In a sense the Cable Route thus really does "provide for the enjoyment of the same in such manner" as Yosemite was before it was a park :)
In any case, and I say this as someone who spends a lot of time in Yosemite, it's best to think of the ditch as a big piece of land that we are sacrificing so that people can have some appreciation of what real wilderness is like and (hopefully) want to protect it. Most certainly nothing going on there is about keeping it preserved in it's original state.
> Jumpers interfere with scenery and the enjoyment of the same.
How is this particular to BASE as opposed to any of the myriad of other things that people are allowed to do in national parks? It seems to me that a horse blocking my view would interfere with scenery, or seeing a line of people walking up the cables, or climbers dotting the peak, or any number of other things would interfere just as much, if not more. A BASE jump is over in minutes. It can take days to climb some of the bigger faces.
I think the jumpers are not impairing them for future generations, but some others are.
More than 60 people have died on Half Dome and very few of them are BASE jumpers. The cable path up there doesn't seem to "maximise preservation".
http://www.yosemitehikes.com/yosemite-valley/half-dome/half-...