I'm afraid that she has misstated the facts. Her great grandfather did nothing more than rent the land for the purpose of grazing cattle. The "preemptive rights" she refers to seem to be the grazing preference given to people who already hold grazing permits which entitles them to special consideration over applicants for grazing permits who haven't acquired a preference. As I read it, this sounds basically like a right of first refusal that prevents someone from leasing grazing rights out from underneath the person currently using them.
Those grazing permits were transferred down, ultimately to her father. In 1993 the grazing rights were up for renewal. For whatever reason he chose not to renew or to continue paying rent for the land he was using.
In other words, stripped of the terms of art used for agricultural grazing issues, his grandfather rented the land solely for the purpose of grazing cattle and the lease for that land was eventually transferred to him, Cliven Bundy. In other words, his grandfather's original lease was assigned to him, something that happens all the time with regular commercial leases. In 1993 he broke the terms of the lease when he stopped paying the rent, which is what the grazing fees are. Ever since then, for the last twenty years, he's been trespassing on that property in violation of the owner's rights.
The mere fact that his grandfather paid money to lease the grazing rights doesn't make the land his just as my paying rent doesn't make me owner of the house I'm renting. That he and his family invested money in building fences and such doesn't change things at all. When a renter builds stuff on the land he's renting, that stuff becomes the property of the landowner; it definitely doesn't make the renter the owner of the land.
I'm sorry but Mr. Bundy is a scofflaw of the first order and is no better than an illegal alien who initially entered legally on a temporary visa and then stayed here after the visa expired.
People lease land to drill for oil, gas, produce coal and minerals. People lease land to erect commercial and residential buildings (usally very long term).
And in this case the rancher essentially leases grazing right from the fedgov for the land where he runs his herds.
He never did own the land, notwithstanding the longevity of his usage.
Many will feel it is heavyhanded for the fedgov to be able to unilaterally insert new conditions into said leasing/fee contract. But behind that is likely legislation, by duly elected representatives of "we the people."
If you as citizen/voter prefer the rancher to have status above the tortoises, you need to convince your fellow voters.
His failure to pay his fees, places him in a weaker position. He has lost continuously in courts.
Like the outcome or not, this is the rule of law in action. We haven't had new offshore drilling in California for decades. I don't like the result, but I have not forced an armed confrontation with government authorities to make the point.
Militia coming to Nevada with arms puts the political right in a weak position, but most of those types are just itching for a chance to show off their bravado, a few in person, and more from the safety of their keyboards.
And the case supporting this rancher is weak at best.