I myself speculated in a recent column: "The danger for Mr Brown is that his government, like Major’s, is now entering a period of what the Germans would call Gotterdammerung – the twilight of the gods. Far from renewing Labour in office, it could be that his destiny is to spend the next two years fighting back the inexorable Tory tide, while Mr Cameron prepares for his inevitable victory."
I have already listed my Top 10 political gaffes - so what's the difference between a gaffe and a misjudgement, you may ask?
Well, it's a qualitative one, really. A gaffe is primarily a one-off mistake, often humorous and with few lasting consequences. The misjudgements listed here, by contrast, are ones that arguably changed the course of history, and certainly adversely affected the careers of those who made them.
Five of them were mistakes made by Prime Ministers in office which either ultimately brought them down or, as in the case of Harold Wilson, set their governments off on the wrong course. Three were mistakes made by people who went on to become Prime Minister before the said mistakes in question came back to haunt them. Two were mistakes made by people who could easily have become Prime Minister had they not made them.
And yes, Callaghan is not only at the top of the list, but is the only politician to appear twice....
1. Jim Callaghan not calling an autumn election, 1978
What happened: Prime Minister Callaghan ducks out of an autumn 1978 election after private polls show it might result in a hung Parliament. The ensuing Winter of Discontent puts paid to Labour's credibility as a governing party and leads to 18 years of Tory hegemony which ultimately removes all vestiges of democratic socialism from the British state.
What might have happened: Narrowly re-elected, Callaghan serves for a further three years as Prime Minister before handing over to Denis Healey, who, buoyed by North Sea oil revenues, goes on to establish Britain as a stable, continental-style social democracy. The defeated Margaret Thatcher is replaced by Francis Pym and relegated to a historical footnote as only the second Tory leader of the 20th century not to become Prime Minister.
2. Enoch Powell playing the race card, 1968
What happened: Enoch Powell, spiritual leader of the Tory Right, makes a speech about immigration prophesying that the streets of Britain will soon be "foaming with much blood." He is immediately sacked from the frontbench by Ted Heath and becomes a peripheral figure on the margins of British politics, eventually joining the Ulster Unionists.
What might have happened: After distinguished service as Defence Secretary in the 1970-74 Heath government, Powell successfully challenges Heath for the leadership in 1975 after his two election defeats. Using his supreme oratorical skills to destroy Jim Callaghan at the Despatch Box in the late 70s, he becomes Prime Minister in 1979 at the age of 66, serving for one term before handing over to his faithful protege, Margaret Thatcher.
3. Tony Blair joining the US-led invasion of Iraq, 2003
What happened: Tony Blair, the most electorally successful Labour leader in history, gambles his career on joining a US neo-con inspired military adventure to get rid of Iraqi dictator Saddam Hussein. Although militarily successful, it later becomes clear that the public has been duped into supporting the conflict by a tissue of lies, destroying their trust in the Prime Minister.
What might have happened: Using his world-class diplomatic skills successfully to keep Britain out of a disastrous conflict, Tony Blair is re-elected by a third successive landslide in 2005 and immediately announces his intention to fight a fourth election in 2009. In spring 2007, Gordon Brown accepts the presidency of the International Monetary Fund, and Mr Blair appoints David Miliband as his Chancellor and heir-apparent.
4. Margaret Thatcher implementing the poll tax, 1987
What happened: Believing herself to be politically immortal after a third successive election triumph in 1987, Margaret Thatcher decides to implement a 13-year-old pledge to reform the rates. Her decision to introduce a flat-rate tax unrelated to ability to pay sparks off a popular revolt which ultimately sweeps her away.
What might have happened: Continuing to see-off all pretenders to her crown, sometimes by deliberately over-promoting them as in the case of John Major, Margaret Thatcher secures a fourth term in 1991, albeit by a narrow margin over Labour whose leader Neil Kinnock antagonises some floating voters with his triumphalism. Despite having vowed to go "on and on and on," she serves for only three more years before handing over to her young acolyte, Michael Portillo.
5. Ted Heath's "Who governs Britain?" election, 1974
What happened: Prime Minister Heath, his authority under constant threat from union unrest, ups the stakes by calling a general election on the theme of "Who Governs Britain?" The voters respond: "Obviously not you," and deliver a hung Parliament with Labour as the largest party. Heath loses a further election the same year before being toppled by Margaret Thatcher.
What might have happened: Heath delays the election until the following year and trumps Labour's calls for a referendum on Britain's membership of the EEC by calling one himself, and leading the "Yes" campaign. With the two votes held simultaneously, the public votes overwhelmingly in favour of staying in and returns a triumphant Heath to No 10 for a further five years. He is still succeeded eventually by Mrs Thatcher, though.
6. Harold Wilson not devaluing the pound, 1964.
What happened: Newly-elected Prime Minister Harold Wilson ignores the good advice of his best economist, Tony Crosland, and decides not to devalue the pound, believing it will merely strengthen the widespread belief among voters and the financial markets that Labour governments always devalue. In 1967, Wilson is forced to devalue, thereby strengthening the widespread belief....
What might have happened: Knowing that it pays politically to get the bad news out of the way at the start of a government's lifetime, Wilson overrides the objections of George Brown and Jim Callaghan and devalues in 1964. Recovering from this initial hit, Wilson establishes for Labour such a reputation for economic competence that he is twice re-elected, in 1966 and 1970, finally passing the baton in 1972 to his long-serving Chancellor, Crosland.
7. Michael Heseltine resigning over Westland, 1986
What happened: Tiring of Margaret Thatcher and her autocratic ways, Defence Secretary Michael Heseltine ignites a row over the fate of a small West Country helicopter company which gives him the excuse to stage a dramatic resignation. But his bid to set himself up as the Tories' king-over-the-water backfires when he is defeated by John Major for the leadership in 1990.
What might have happened: Remaining studiously loyal to Mrs Thatcher throughout the late 1980s, Heseltine's steadfast support in the face of a bitter attack from Sir Geoffrey Howe is widely-held to have headed-off a potential leadership challenge in 1990. After Thatcher is gently persuaded by the men in
8. Jim Callaghan opposing In Place of Strife, 1969
What happened: Big Jim takes on Barbara Castle over her plans to curb union power and wins. His gamble in appointing himself as Labour's Keeper of the Cloth Cap appears to pay off when seven years later he wins the leadership, but nemesis awaits in the shape of the still-unreformed unions who sweep away Callaghan's premiership in the Winter of Discontent.
What might have happened: Capitalising on the public acclaim engendered by his tough stance against the unions, Harold Wilson wins a comfortable victory in the 1970 General Election. Overtaking Asquith's 20th century record of continuous service as PM in 1972, Wilson hands over the leadership to his long-time heir apparent, Roy Jenkins. But tiring of the endless battles with the Labour left, Jenkins quits in 1977 to become President of the European Commission, leaving Callaghan in charge.
9. John Major entering the ERM, 1990
What happened: After years of saying "no, no, no" to British membership of the European Monetary System, Margaret Thatcher is finally prevailed upon to enter by her new Chancellor, John Major, at a rate of 2.95DM to the pound. The level proves unsustainable, and on Black Wednesday in 1992, Prime Minister Major is forced to withdraw from the EMS and effectively devalue sterling.
What might have happened: Siding with Mrs Thatcher against her pro-European Foreign Secretary, Douglas Hurd, Major decides the time is not right (or ripe) for ERM entry. Hurd and Geoffrey Howe resign, precipitating a leadership challenge by Michael Heseltine. Thatcher is brought down, but Major emerges as Prime Minister and reaffirms his decision to stay out despite sustained Labour criticism. Two years later, his stance is vindicated and the Tories' reputation for economic competence reinforced.
10. Gordon Brown not challenging John Smith, 1992
What happened: Gordon Brown, seen as the natural leader of Labour's modernising faction, declines to challenge John Smith for the party leadership in 1992. Over the ensuing two years, he is eclipsed by his younger rival Tony Blair, and is forced to stand aside in his favour when Smith unexpectedly dies in 1994. Blair goes on to serve for 13 years as leader, ten of them as Premier.
What might have happened: Brown loses to Smith, but establishes himself as the clear heir apparent. He is elected unopposed in 1994 on Smith's death and become Prime Minister in May 1997, winning again in May 2001 before handing over to Tony Blair after ten years as leader in 2004 as previously agreed between them. Blair goes on to win another landslide for Labour in 2005, but faced by the prospect of a Tory resurgence, embarks on a radical plan to renew the party in office under the banner "New" Labour.
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