During his second term in office, U.S. President Barack Obama is likely to continue the implementation of his ambitious arms control agenda. In the European context, this will require further work on the redefinition of the extended deterrence relationship with the European NATO allies, which currently involves U.S. nuclear weapons stationed in Europe. However, the programme of work cannot be limited to the nuclear file, as at present in Europe both missile defence and conventional arms remain important subjects, both in need of innovative arms control approaches. The role of Europeans does not have to be limited to merely supporting U.S. actions. They can provide their ideas and also take a leadership role in some areas. The lack of a unified position of Europeans can, however, block or obstruct U.S. initiatives.