3/5 are standard while 2/5 are not necessary IMHO but given those 2 were international flights the departing country would probably prefer not to seen as lax on searches if an incident occurs. Of course my comment is not a judgement on the effectiveness of those additional searches.
1) Upon entry to the secure area in Beijing
Std airport security ...
2) Upon entry to the jetway in Beijing
International flight "extra layer" - some would say not needed if primary was "good enough"
3) After exiting the flight to Narita (before getting to the gate area)
Std airport security for international PAX entering the airport and transferring to another flight
4) Upon entry to the jetway in Narita
International flight "extra layer" - some would say not needed if primary was "good enough"
5) Upon exit of immigration/customs in Atlanta before my flight back home.
Std airport security for international PAX entering the airport and transferring to another flight
Exactly what weapon or other dangerous material was I suppose to have picked up between the jetway in Beijing and exiting the plane in Narita?
In all seriousness one never knows theses days ...