When creating art in a public space, an artist must consider the possibility of vandalism, and incorporate either the avoidance or the embrace of it into her design and/or careful placement. Artists that make work that is not intended for a public space usually do not take the possibility of vandalism into account. Most museums that show this type of work have attendants to make sure that no one disturbs the art in the space.
I am reminded of the way that a statue of Margaret Thatcher in the UK, the infamous Prime Minister, was actually decapitated as an act of political protest against her policies. Certainly, the public display of art is to welcome a whole host of different responses to it, some of which will be negative. However, at the same time, this appears to be a necessary element of free speech and of art's ability to provoke and get a reaction. Whilst many museums do an excellent job of protecting art, unfortunately, it will never be enough to deter the most determined of individuals.
Art on display in museums and galleries is carefully guarded against vandalism and theft by people and devices that ward off the possibility of willful (or accidental) harm. Outdoor artwork runs the greater risk because guards can't practically be posted to safeguard it at all times. Our era is different than previous eras because to a very large extent restraints are broken down, so the tradition of respect and admiration for outdoor artwork has weakened--it was this tradition that in large part protected art work from vandalization, as cities like Bern, Switzerland, attest.
The thing about art is that it is done either purely for private enjoyment or for public appreciation in some form. Once art is put on display for the public, it automatically takes on risk. Some people will like it, and some people will not. Some people will appreciate it and may even want to pay to own it; some people will not and might even do something drastic to show their dislike; and some people see it only as an opportunity to be destructive. Unless we want to hide it all behind plexiglass, public displays of art are going to be at some risk, unfortunately.
I think that to protect art people need to have a greater understanding and appreciation for it. Once people learn to accept art for what it is, a person's reflection on life, that they would realize that they are destroying personal belief and thought.
I use the story "The Lottery" to teach about the importance of acceptance- regardless if one agrees with something, they should accept it as another person's right.
I would think that the same premise could be used to protect all communication-art included.
In some of the most crime-ridden neighborhoods in my city, there are beautiful and creative murals adorning the walls of some buildings and businesses. They were painted by graffiti artists with the consent of the owner, and some are so beautiful and valued by the community that no one vandalizes them. This is especially true of those with religious images. So I think the best way to prevent vandalism is to create such a social stigma, so much peer pressure against it, that vandals will choose not to most of the time. I think that is much more effective than any law or security guard. They simply become another symbol of authority to challenge.
The vandalism of art work is one of the most senseless crimes I can imagine. If you have ever been to the Louvre in Paris, you will see that the Mona Lisa is protectively encased and can only be viewed from a distance in the presence of armed guards. Such is not the way to enjoy art, but it is the only way such a masterpiece can be preserved in today's world. I like the idea mentioned in Post #2, with the larger work force of students being used, but a determined saboteur will probably not be deterred by such numbers.
Yes, tightening security is the most obvious answer. Perhaps, though, as a society we could help decrease vandalism by starting young. If parents would instill in their children a healthy respect not only for other people's things, but also for the aesthetic value of art, when they get to vandalizing age, they may not have any desire to destroy the artwork around them.
The most simple answer to this is to tighten security. This becomes a challenge, though, with rising costs, less public funds, and everyone, including museums running for financial cover. Increased technology and surveillance efforts become difficult when funds are limited.
With this, the Indianapolis Museum of Art took a different approach. They argued that increase in funding and surveillance was not the answer. Rather, they dismissed their security guards and took 100 students from a local university and used them in conjunction with a federal work study program to assume the responsibilities of monitoring art work and protecting the art work at the museum. It's a fairly innovative approach. Increasing the physical presence of security guards or security bodies in rooms with artworks with being able to defray the cost to students' federal work programs is fairly unique. Their approach is to increase manpower by throwing more people at the problem. The rationale is that it is moder difficult to desecrate art samples if there are two or three bodies standing there, whose job is to prevent a potential offender from doing so. Additionally, it makes it more difficult with so many people to coordinate an "inside" job at vandalism and theft because there are more individuals to accommodate. It might not be the most news grabbing headline approach, it shows how thinking outside of the box in tough economic times has impacted museum protection of valuable artwork samples.