Over five years, the Government ruthlessly cut defence spending, kept out of the war in Syria and chose to take a back seat in the European Union. As a result, Britain has been largely watching from the sideline as the United States fights Isis (Islamic State) and its EU partners shape events in Ukraine or grapple with a migrant crisis in the Mediterranean.
The House of Commons defence committee in a report this year on the Royal Air Force's role in the campaign against Isis called it "strikingly modest".
It said: "This is a relatively minor commitment involving eight of Number 2 Squadron's 16 Tornadoes ... it seems only two are flying at a time."
Britain is flying Reaper drones armed with Hellfire missiles as part of surveillance missions over Syria.
Observers say there are scant signs Britain's sense of drift will change after the elections, and the consequences for its fabled "special relationship" with the US could be far-reaching.
"UK foreign policy is best described as fragile," says Paul Cornish, a specialist at the RAND Europe think-tank in Cambridge. "The UK is considered by some to have played little more than a supporting role in recent European and international security crises."
Conservative Prime Minister David Cameron - under pressure from the anti-Europe UK Independence Party - has promised that if re-elected, he will stage a referendum by the end of 2017 on Britain's continued membership of the EU. As last year's referendum on Scottish independence showed, such ballots can be hugely divisive, nor do they always resolve the issue.
Under Labour and the pro-European Liberal Democrats, who could be Labour's coalition partner if they manage to retain enough seats, there would be no referendum. But that, too, would fail to resolve a clamour to hold one, and the Government's hands on Europe would remain tied.
"Either way, the issue of British membership [of the EU] would be a live one," said Arnand Menon, professor of European politics at King's College London. At the heart of Britain's problem is "a crisis of identity", Menon said.
Some experts trace Britain's europhobia to 1940, when the country was saved from Nazi invasion because it was an island.
What began as insularity has been fanned, among English Conservatives especially, into hostility towards European integration projects deemed superfluous, bureaucratic or damaging to national sovereignty. Since national careers are built in Westminster, not Brussels, few leaders speak out publicly about the benefits of EU membership - something the business lobby, alarmed at the prospect of an exit, is now starting to do. Under Cameron's ambivalence towards the EU, Britain has withdrawn from the top table, leaving France and Germany to steer discussions. Worse, Cameron has caused irritation in Brussels with his demands for reform, some of which are viewed as grandstanding or daft.
Britain's semi-detached stance has coincided with cuts in defence spending, mirroring the distaste for the costly campaigns in Afghanistan and Iraq under the former Labour leader, Tony Blair.
Even though the Conservatives are traditionally hawks on defence, Britain will have been deprived of an aircraft carrier for three years until a new ship, HMS Queen Elizabeth, enters service in 2017. The Government has reduced the RAF's number of interceptor squadrons to seven and the Royal Navy to a mere 14 warships, and left just 82,000 men and women in the army, down from 102,000. The axing of Britain's maritime patrol aircraft means the country now has to appeal to its Nato allies for help whenever a suspected Russian submarine nears its waters.
While Britain has refused to guarantee a defence budget of 2 per cent of gross domestic product in line with Nato guidelines, France - a country of comparable economic size - has not only persistently met the target but intends to go beyond it. Last week, President Francois Hollande cited "threats at home and abroad" as he announced the defence budget would rise by a total of more than 10 per cent between 2016 and 2019, saving 18,500 out of 34,000 job cuts that had been planned in the military.
The aftermath of the election will be closely watched by America, according to Daniel Keohane at FRIDE, a European think-tank based in Madrid.
"If recent trends in British foreign policy - falling defence spending, relative absence from key international security challenges and moodiness towards the EU - continue, then those voices in Washington already questioning the UK's relevance will surely strengthen," Keohane said. "And if the UK were to leave the EU, [it] would become a useless ally for the US."
Candidate barred after gun threat
Britain's anti-EU, anti-immigration UK Independence Party has suspended a parliamentary candidate for apparently threatening to shoot a rival.
Robert Blay, a candidate for North East Hampshire in southern England, was filmed by the Daily Mirror insulting Conservative rival Ranil Jayawardena and calling him not British enough.
In the video, Blay remarked that Jayawardena had been tipped to be Britain's first Asian prime minister.
"If he is I will personally put a bullet between his eyes," Blay said. "If this lad turns up to be our prime minister I will personally put a bullet in him. That's how strong I feel about it ... I won't have this f****er as our prime minister. I absolutely loathe him."
A Ukip spokesman described Blay's comments as "abhorrent" and said he had been suspended from the party.
Ukip, which campaigns for Britain to leave the EU, has fought to shake accusations of racism after prominent members and candidates were caught up in scandals over their views.
Jayawardena, whose father migrated from Sri Lanka, is expected to win the constituency. In the footage, Blay said Jayawardena's family had arrived in the country too recently and described him as "not British enough to be in our Parliament".
Referring to the Conservative party colour of blue, Blay said: "I've always said in my constituency you could put a monkey out there with a blue rosette on and it would win."
A Ukip spokesman said, "Any comments of this sort have absolutely no place in British politics or public life, and the party would like to take this opportunity to apologise to Mr Jayawardena for any distress caused."
Ukip has 14 per cent support, according to a BBC poll of polls.
The kingmakers
Nick Clegg, 48, Liberal Democrats
The Deputy Prime Minister's experience in government has been damaging and polls suggest he and his party are so unpopular that he could lose his seat. If he holds it, Clegg has not ruled out alliances either on the right or the left.
Nigel Farage, 51, UK Independence Party
Farage is battling for his political future, with commentators saying his populist campaign has run out of steam. Anti-Brussels and anti-political correctness, Ukip topped the polls in European Parliament elections in 2014.
Nicola Sturgeon, 44, Scottish National Party
The steely and polished Scottish First Minister has become one of the most talked-about figures in the campaign thanks to her performance in election debates - even though she is not running for a seat herself. She has cut a swathe through the UK's male-dominated politics, criticising austerity and advocating the SNP as a "progressive force" with quick humour.
- AFP
