"The war on terror is not working," Labour leader Jeremy Corbyn said, as campaigning resumed after a three-day break following the attack. Organisers preceded Corbyn's speech with a minute's silence to honour the 22 people who died in the bomb blast.
In the address, Corbyn linked Britain's foreign wars to terrorist attacks but stressed the connection "in no way reduces the guilt of those who attack our children". He said: "Many experts, including professionals in our intelligence and security services, have pointed to the connections between wars our government has supported or fought in other countries and terrorism here at home".
Corbyn, a longtime critic of the Britain's wars in Iraq and Afghanistan, also pledged that if he were prime minister, troops would only be deployed abroad if there was a clear need, proper resources and a plan for "lasting peace". His opponents wasted no time in accusing him of trying to politicise the attack.
"I have been here at the G-7 working with other international leaders to fight terrorism," May said on Saturday after a summit meeting with top European leaders and US President Donald Trump. "At the same time, Jeremy Corbyn has said that terrorist attacks are our own fault. There can be no excuse for terrorism."
Boris Johnson, Britain's Foreign Secretary, said that Corbyn's position was "absolutely monstrous". Liberal Democrat leader Tim Farron said that Corbyn was trying to score a "political point" and that he disagreed with his timing.
Corbyn responded to the criticisms, saying that he wasn't defending the "indefensible" Manchester attack but was reflecting the view that countries that want a secure future need to reflect on foreign policy. "Any sensible government has to look at what is happening in Libya, a huge ungoverned space and apparently a source of some awful extremism," he said. The attacker, Salman Abedi, 22, was born in Manchester to Libyan parents and had travelled to Libya ahead of the bombing.
Britain's right-wing tabloids ripped into the Labour leader. "This is a man who, for years, has been one of Westminster's foremost apologists for terrorism," wrote Guy Adams, a columnist in the Daily Mail.
Although the Conservatives lashed out at Corbyn's remarks, they could also galvanise his base. Corbyn's speech "will outrage many Conservatives, but if his aim is to mobilise his core left liberal vote, then it could work," said Tim Bale, a politics professor at Queen Mary University of London. "Now, how that will play with the majority of voters is another matter."
Recent polls have shown the Conservatives' lead significantly narrowing.
When May called the snap election last month, her opponents were weak and fractious. One pollster gave her Conservative Party a towering 23-point lead. But a YouGov poll on Saturday showed the Conservative Party's lead had slipped to five points - a dramatic shift that would put Labour on track to gain seats, something few political commentators expected weeks ago. A YouGov poll yesterday had the Tory lead at seven.
Many attribute the shift to Labour's successful manifesto launch and a controversy in the Conservative Party over its plans - since abandoned - to cut social benefits for the elderly.
It's possible, analysts say, that the Conservatives could inch back up in the polls following the terrorist attack as the narrative shifts away from their recent difficulties to focus on May's leadership and security issues.
Before becoming Prime Minister, May served for six years as Britain's Home Secretary. She is also seen as the leader most likely to keep Britain safe from terrorist threats.
"May's recent difficulties will now be overtaken by events," wrote Mujtaba Rahman, an analyst with the Eurasia Group, in a briefing note. He said that the election campaign will shift to a "stronger focus on leadership, where Labour is at a strong disadvantage with Jeremy Corbyn in charge".
Bale agreed that conventional wisdom suggests May could benefit but also warned that it could backfire if it is proved that there were failings in the security services.
"Normally, there is a degree of rallying around an incumbent or president or prime minister in this situation. But there are downside risks, as well, if investigation proves the security system could have spotted this man earlier and can pin that on lack of resources," said Bale.
But whatever way the pendulum swings, he said, "it's difficult to believe the election campaign will be the same as it might have been before the bomb went off".
