Yes, the private security sector should take an active role in preventing terrorism – especially considering how there are more private security guards in most countries compared to the number of law enforcement individuals. In fact, that is exactly what the post-9/11 Policing Project is (IACP initiative). Law enforcement and private security companies present the same degree of threat to terrorists, which is why they are considered to play a critical role in counter-terrorism. Terrorists attack law enforcement just as frequently as private security companies, which means that preventing them from taking action would mean that security companies would be left unprotected.
Another major reason why private security should take part in counter-terrorism is the resources they tend to have. In most cases, counter-terrorism evaluation research is conducted by private companies, and because of their budget, their research is more accurate. On a small scale, private companies are often given strategic intelligence on how to operate and avoid terrorism. However, as far as rescinding to terrorist attacks is concerned, security companies shouldn’t get involved. Theyshould stay defensive since security companies often don’t have the infrastructure to wage and sustain an all-out war against terrorists.
In many countries, security companies take a defensive approach towards terrorism, i.e., they tend only to react when probed or when the asset, personnel, or property they are protecting is under attack. Most often, governments also rely on the same and therefore strategize accordingly. If there is suspected terrorist activity anywhere, governments just inform the security company and leave it at that. However, in the US, security companies often take part in offensives against terrorism as well.
These are often referred to as “outlaw private security firms” since they are also often found hunting terrorists down.
Having said that, it is equally important to note that compared to other countries’ security officers and companies, US security personnel and companies are much better prepared for counter-terrorism. For example, security guards in the UK are most often not allowed to carry lethal weapons, while security guards in the US don’t just carry fully loaded weapons (even fully automatic rifles), they are also allowed to use them in the event of a terrorist attack to support local law enforcement until counter-terrorism task forces don’t arrive.