I agree with the military having unlimited access to any site necessary for training. Therefore they were wrong to deny the U.S Army access to the Hawaiian cultural sites. They deserve to have unlimited access since they are responsible for security in each and every place. If anything happens, they will be around to sort it out.
The military should respect the indigenous people of the place they are occupying. They need to learn to behave like guests. They should be polite and civilized, and respect the owner of the places that they are visting. It is not their home, and they should be polite and kind.
The military should absolutely not have unlimited access to any site for training purposes. This is a fairly large country, and even given that Hawaii is an island, those culturally significant sites can't be the only places on it where the military can conduct training. The military shouldn't be allowed to block access to sacred sites.
While the United States military should have many allowances, it should not have unlimited access to training locations. The military should take advisement when it comes to historical and cultural significance before creating a training location. I would also keep in mind that it has so many places already at it's disposal and that with the resources we have today can recreate almost anything about the location that would be special for the type of training they are trying to achieve.