 In the first place, we seriously doubt that the First Amendment requires the Park Service to permit a demonstration in Lafayette Park and the Mall involving a 24-hour vigil and the erection of tents to accommodate 150 people.Furthermore, although we have assumed for present purposes that the sleeping banned in this case would have an expressive element, it is evident that its major value to this demonstration would be facilitative.Chief Justice Warren E. Burger delivered a short concurring opinion that he begins by discussing the language of the case "could hardly be plainer in informing the public that camping in Lafayette Park was prohibited."