Lethal drone that's flown over America? (6,3)

I believe the answer is:

killer bee

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'that's flown over america?' is the definition.
I can't tell whether this defines the answer.

'lethal drone' is the wordplay.
'lethal' becomes 'killer' (I am not sure about this - if you are sure you should believe this answer much more).
'drone' becomes 'bee'.
'killer'+'bee'='KILLER BEE'

Can you help me to learn more?

(Other definitions for killer bee that I've seen before include "Aggressive type" , "Aggressive insect" , "Honey-producer" .)

I've seen this clue in The Telegraph.

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