that, to continue, had to be subsidised by other workers. The Union split. In the end, almost all the coal mines were shut down. Britain turned to its vast reserves of North Sea gas and oil, which brought in substantial tax and export revenues, to fuel a new economic boom. After the economic boom of the 1980s, a brief but severe recession occurred between 1990 and 1992, mostly under the ministry of John Major; who succeeded Thatcher as Prime Minister and Conservative Party leader in November 1990. The pound was ejected from the Exchange Rate Mechanism on Black Wednesday in September 1992, an event which was humiliating for the Conservative government but which helped boost the recovery. The rest of the 1990s saw a period of continuous economic growth that lasted over sixteen years and was greatly expanded under Blair's New Labour government following his landslide election victory at 1997 general election, with a rejuvenated Labour Party abandoning its commitment to old policies like nuclear disarmament and nationalisation of key industries, and no reversal of the Thatcher-led union reforms. Many traditional Labour supporters were unhappy with Blair abandoning socialism and the restructuring of Clause IV in 1995; effectively tearing up the constitution which had put socialist values and common ownership of industry at the heart of party policy for nearly eighty years. Blair promoted the Labour Party as "New Labour", a social democratic centrist party for the 21st century which promised to inject new life into Britain; with investment in education made a key priority. Since 1997 Tony Blair and New Labour Tony Blair became the Leader of the Labour Party in 1994, and served as Prime Minister from 1997 to 2007. With Gordon Brown, he founded the movement known as New Labour. In domestic policy, Blair sought to modernise Britain's public services, encourage enterprise and innovation in its private sector and keep the economy open to international commerce. The Northern Irish, Scottish and Welsh devolutions took place under his premiership. Kavanagh argues that by the 1980s, left-wing or socialist tendencies in the Labour Party divided the party and united its enemies: Blair moved the Labour Party in new directions, minimising the left-wing or socialist factions. He thereby broadened the appeal to professionals and middle-class voters in "Middle England", who had traditionally voted Conservative. Blair was also anxious to escape from the Labour Party's reputation for "tax-and-spend" domestic policies; he