resistance movement. Militant nationalism Mainstream nationalism in Wales has been constitutional, and in Wales a pacifist instinct of Welsh nonconformist persisted before and after 1939. However there have been some militant movements in Wales described as Welsh militant nationalism. In 1952 a small republican movement, Y Gweriniaethwyr ("The Republicans"), were the first to use violence when they made an unsuccessful attempt to blow up a pipeline leading from the Claerwen dam in mid Wales to Birmingham. In the 1960s two movements were established in protest against the drowning of the Tryweryn valley and the 1969 investiture of Charles, Prince of Wales: Mudiad Amddiffyn Cymru ("Movement for the Defence of Wales", also known as MAC) and the Free Wales Army (also known as FWA, in Welsh Byddin Rhyddid Cymru). MAC were responsible for numerous bombing attacks on water pipelines and power lines across Wales. On the eve of the investiture two alleged members of MAC, Alwyn Jones and George Taylor, died when the bomb they were planting outside a Social Security Office in Abergele exploded. The late 1970s and the 1980s saw an organisation calling itself Meibion Glyndŵr ("sons of Glyndŵr") responsible for a spate of arson attacks against holiday homes throughout Wales. In the 1970s, a Welsh Socialist Republican Army arose, whose initials in Welsh spelt out the English word "DAWN": the Welsh Army for the Welsh Republic (WAWR). See also In Wales Welsh independence Welsh devolution List of movements in Wales Cofiwch Dryweryn Similar nationalist movements Irish nationalism Irish republicanism Scottish independence Scottish nationalism Cornish nationalism Cornish self-government movement Breton nationalism Celtic movements Celtic Congress Celtic League (political organisation) Celts (modern) References Sources/bibliography Clewes, Roy (1980), To dream of freedom: the struggle of M.A.C. and the Free Wales Army. Talybont: Y Lolfa. . Butt Philip, Alan. The Welsh question: nationalism in Welsh politics, 1945–1970 (University of Wales Press, 1975). Davies, John (Ed.) (1981), Cymru'n deffro: hanes y Blaid Genedlaethol, 1925–75. Talybont: Y Lolfa. . A series of essays on the history of the first fifty years of Plaid Cymru. Davies, R. R (1997) The Revolt of Owain Glyn Dwr. (Oxford UP, 1997) . Gruffudd, Pyrs. "Remaking Wales: nation-building and the geographical imagination, 1925–1950." Political Geography 14#3 (1995): 219–239. Jones, Richard Wyn, and Roger Scully. Wales says yes: devolution and the 2011 Welsh referendum (University of Wales Press, 2012). Morgan, Kenneth O. Rebirth of a nation: Wales, 1880–1980 (Clarendon Press,