review petitions submitted by the public. An early petition sought clarification of government policy in relation to the use of Irish airspace by foreign military aircraft. In 2013–16 the committee held discussions with the petitioners, government members, the Secretary General of the Department of Foreign Affairs and Trade, and academics, and issued a report, which stated: The Joint Committee note the lacuna between what is understood by the citizens by neutrality and what is the position. Accordingly, the Joint Committee recommend that the Dáil and Seanad debate the matter of neutrality with a view to the holding of a Referendum so that the will of the people can be determined. The 2011–2016 Fine Gael–Labour government published a 2015 foreign policy review which stated, "Our policy of military neutrality remains a core element of Irish foreign policy." The 2015 defence white paper presupposed "a policy of military neutrality which is characterised by non-membership of military alliances and non-participation in common or mutual defence arrangements", while engaging for peacekeeping purposes with the EU and NATO. An "Institute for Peace Support and Leadership Training" is to be established at the Curragh Camp; defence minister Simon Coveney said trainees from "non-neutral" countries would be permitted to enrol. Ireland joined the EU's Permanent Structured Cooperation (PESCO) at its establishment in December 2017. The Fine Gael-led government said it would participate on a case-by-case basis and membership did not compromise neutrality. Fianna Fáil supported membership; Sinn Féin, the Greens, Solidarity, and People Before Profit opposed it; the Labour Party had reservations. In March 2018 Ireland expelled a Russian diplomat in protest at the poisoning of Sergei and Yulia Skripal in the UK. This decision was supported by Fianna Fáil and Labour and opposed by other opposition parties as compromising neutrality. Recent conflicts 2001–2021 Afghanistan War Despite its policy of neutrality, Ireland has supplied the NATO-led ISAF mission in the 2001–2021 Afghanistan War with a running total of 120 Irish troops as trainers. The troops are provided under United Nations mandate. As at 8 June 2011, there were seven personnel there. 2003 invasion of Iraq The Fianna Fáil-led government did not take a position on the 2003 invasion of Iraq. Ireland, then a member of the UN Security Council, voted yes to Resolution 1441, which threatened "serious consequences" if Iraq did not comply with weapons inspectors. Some United States Air Force planes were allowed to refuel at