There is likely to be an active shooter had an air force base similar to Andrews Air Force Base in near future because most Air Force bases are gun free zones, making it an easy target for a shooter to commit horrible acts. Arming soldiers on bases and other military installations would be an incredible deterrent two active shooters.
Although there wasn't an active shooter this time it isn't out of the question to happen in the future. Security needs to be increased in almost all aspects of the US to ensure things like this don't happen. It can't be said one way or the other if it will happen or not.
With the constantly changing security situation worldwide, it is important that all official and non- official locations (public and private) prepare safety and risk-assessment activities to address any glaring deficiencies in their current safety plans. While we cannot know for certain if there is likely to be another similar situation in the future, it is important to always be prepared.
They keep an eye out on the bases, so I think they will be in the clear in the near future. The military might even choose to keep any such situations to themselves instead of informing the public. Officers might choose to keep such occurrances under wraps using military confidentiality.