Michael Ron David Kadar, 18, who has joint US-Israeli citizenship, allegedly used the internet to make hundreds of hoax calls in the US, UK, Canada, New Zealand and Australia.
Prosecutors say he often used software to disguise his voice as a woman's.
He is also accused of trying to extort money from a US senator.
Israeli prosecutors say Mr Kadar made more than 2,000 threatening calls to schools, airports, police stations and hospitals over a two-year period.