My condolences. This is a new kind of enemy, and the traditional approach of stationing 2 guards at the entrance is not effective. You cannot have a general solution to this kind of threat, rather, every public institution and churches (starting with those in n eastern and coast ) should evaluate their exposure levels and seal any obvious loopholes. For instance I remember in college and high school main access doors for dormitories used to be open 24/7. This should not be the case anywhere today. Nowadays, developers of major buildings and mixed use developments contract specialists to advise on what security infrastructure to put in place so as to neutralize current and future threats. Let all public institutions take it upon themselves to analyse their own exposure levels, even if it means bringing in specialists. Govt will not help.