Translate the following English sentence to French:
"But we will only be able to take advantage of these well-trained technicians and qualified employees if the idea - which has not been thought through - of having a system of green cards is finally dismissed."
Mais nous ne pourrons profiter des talents des techniciens et des spécialistes qui ont reçu une bonne formation que lorsque nous disposerons de la carte verte, idée non encore aboutie.