Metal detectors, in conjunction with bag checks have been a presence in the parks now for quite some time. The reality of the troubled world that we live in bleeds over even into Disney from time to time. Nobody is immune.
In an effort to reduce the time that screening takes at Magic Kingdom, Disney has moved the centrally located security measures to the transportation spoke of the process. Guests used to find security screening at the front of the park upon arrival. Now, guests are screened at the Polynesian, Grand Floridian or Contemporary Resorts before boarding the monorail. You also must get screened as you enter from the bus area.
The jury is still our wether this move is a positive experience for park goers. It helps streamline the process of getting in to the Magic Kingdom in the morning. I am afraid that the excess screening when travelling the monorail to other resorts will cause more frustration and delay for guests staying and dining at monorail resorts.