If you have a responsibility for people, be it an employer, club, bar or small business then you also have a responsibility for their safety , whilst most organisations take the threat of fire seriously and take steps to negate the threat (Drills, Alarms, inspections etc.) Not so many workplaces have steps in place to deal with acts of Terrorism. If you have an office or workplace full of people do you know what to do if the worst happens? You should at least plan for it? If your the boss, during an incident it's quite likely the staff will be looking to you. Don't let them down! This of course applies not just to offices but schools, supermarkets and places where people gather.
Whilst it's realistic to say a determined armed attacker is hard to stop in the act (by unarmed civilians), it's also true to say that attackers are easier to detect in their planning stages, the terrorist attack cycle starts with planning, surveillance and then rehearsals, often this terrorist / criminal surveillance is unsophisticated and presents its self as a great point at which to “Break the cycle” Security guards and security managers should have robust counter surveillance plans and mitigation measures in place so as to detect any possible watchers. Within the City of London this is more common, but outside this area not so much.
Do yourself a favour this Monday morning, Take a look at your building security plans, ask your building security guard what they are personally doing to ensure your safety, Do they have anything in place to deal with an act of terrorism? Do they know what the Terrorist Attack Cycle is? Are there procedures in place for negating the threat and breaking the cycle? If there aren't then ask them to implement them, if they can't do that effectively then change to a provider who can, after all, you wouldn't carry on employing a fire safety officer who constantly let the smoke alarm batteries run down. Would you?