Read somewhere that the Hamas slogan was "Israel says no. America says no."
They will have to be pretty productive to make up for the donations to the PA they stand to lose if they remain a terrorist organization. 60% of PA funding comes from foreign aid (via
Belmont Club):
US $368 million
EU $338 million
Arab League $197
Britain $43 million
Italy $40 million
Sweden $32 million
Germany $27 million
Spain $17 million