For the most part, archeological digs are done on entire areas that have been covered by newer buildings or just by the sands of time. They are done on sites where the information about the place isn't readily available and when there is information to be learned. Things now are done in a much more modern manner. Arlington National Cemetery is not going to be covered by the sands of time unless we have some sort of cataclysmic event and hundreds or thousands of years later the people don't know what happened, what was located where, etc. And then they may very well dig up some of the cemetery, but I have to think its really quite unlikely to happen any time soon and if it does it won't be in a disrespectful manner. To ignore history is a terrible mistake. We have learned a great deal from all types of archeological sites, including graves. Especially from graves tens of thousands of years old. Those people didn't leave us libraries of documents about their lives. Seeing how they treated their dead and the things that were buried with them really does teach us a great deal. I guess I just don't see it as a desecration, but more of an information gathering expedition.