Answer: continue to protect by positioning themselves in key areas
Explanation:
Security guards in the current still maintain the practice of positioning themselves in key areas to be able to counter whatever threat that might come to a monarch.
They are however, much more adept at figuring out threats these days due to the use of technology. With technology for instance, the area under surveillance has expanded drastically due to the use of communications technologies including CCTV and wireless earpieces which allow the guards to communicate with each other instantly.
In the past they could watch the immediate environment, today, they can watch entire neighbourhoods around the building of interest.