This is a great question and I hope someone can come up with a definitive answer.
Off the cuff I think that the BLM land is land that is controlled by the United States FEDERAL government. The Bureau of Land Management is the department that is in charge of these lands. Their goal is to manage the lands so that the public can use them while at the same time they are not destroyed for future generations. They are, in effect, protected lands, though generally not of any particular good use. Many people use BLM land to graze their cattle and sheep. The ISDRA is land under the control of the BLM that they've designated an off road use area. That is, they've decided that the best use for this land for all concerned is that it be used for off road recreation. Just like they have designated the area NORTH of 78 as a nature hike area.
The difference between ISDRA and Ocotillo Wells is that Ocotillo Wells is controlled by the State of California and not the Federal Government.
I've mentioned that one form of fighting back on this issue would be to get the State of California to kick the Federal Government out of here. Not sure how effective that would be but I know that the State people do an AWESOME job over at Ocotillo Wells and I am sure would do just as good a job here in the ISDRA!
Hopefully someone can come back and correct me wherever I was wrong... I was writing off the cuff and don't really have all the facts.
Vor
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