In their cooperation with Americans, Europeans managed to put pressure on Iran while making sure their red lines were respected.
In 2010, Europeans were able to maintain a united front with Americans on Iran, the most prominent case of nuclear proliferation, to further their objectives. They jointly insisted that Tehran observe its obligations under the Non-Proliferation Treaty (NPT) and comply with UN resolutions asking for the end of uranium enrichment. But in the context of this cooperation, Europeans also had three specific objectives vis-à-vis Americans: to increase both sanctions and incentives; to go through the multilateral process rather than a purely transatlantic format, in spite of the added delay and necessary concessions to Russia and China; and to prevent the imposition by the US of extraterritorial sanctions, which they opposed both out of principle and in order to protect European firms.
Europeans met most of these objectives. They worked with Americans within the UN framework and, on 9 June, the Security Council adopted Resolution 1929. Although it was not unanimous (Turkey and Brazil voted against it), and was watered down, the resolution provided the EU and the US with the legitimacy they needed to enact their own harsher measures against Iran – which the EU did on 26 July. Earlier in the year, High Representative Catherine Ashton strongly protested against bills in Congress that threatened extraterritorial sanctions for companies that supply gasoline to Iran. The bills were not enacted but, in September, several European companies pledged to end their investments in Iran and avoid new activity in the country's energy sector, thereby reducing tensions and satisfying governments on both sides.
If they were remarkably united on Iran, with a leading role for Ashton in negotations with Tehran, Europeans were also united and effective at working with Americans at the NPT Review Conference in May, which produced a satisfying result. However, on the other main case of nuclear proliferation – North Korea – they were largely absent (see component 9).