As Western powers were taken aback by the incredible speed with which the Taliban seized power in Afghanistan, there is now widespread concern as to how the new regime will conduct its affairs in a number of areas.
High among those fears are that terror groups like Al-Qaeda will be afforded the opportunity to rebuild and once again pose a threat in Europe and North America.
Here in Ireland the threat of a terror attack is believed to be extremely low, but the European Union will be worried about any increased risk arising from the Taliban resurgence in Afghanistan.
In the deal reached last year with the US, the Taliban agreed not to let groups - including Al-Qaeda - to use Afghanistan as a base to threaten the security of the US and its allies. Whether this commitment will be honoured remains to be seen.
Earlier this week, British Prime Minister Boris Johnson told the House of Commons that the Taliban will be judged on its actions rather than its words.
And in a televised address on Monday, French President Emmanuel Macron said that Afghanistan must not again become the "sanctuary of terrorism" it was until the US-led invasion two decades ago.
At the same time, US President Joe Biden said on Monday that America's "only vital national interest" in Afghanistan had been preventing an attack on US soil.
He said the terror threat has "metastisized well beyond Afghanistan", citing al Shabaab in Somalia, Al-Qaeda in the Arabian Peninsula, al-Nusra in Syria and the actions of ISIS in Syria and Iraq over the last decade.
"The Taliban regularly consulted with Al-Qaeda during negotiations with the United States"
Nevertheless, it is believed that ties between the Taliban and Al-Qaeda remain close.
A report from the UN Security Council in May 2020 said that the senior leadership of Al-Qaeda remains present in Afghanistan.
It said: "Relations between the Taliban [..] and Al-Qaida remain close, based on friendship, a history of shared struggle, ideological sympathy and intermarriage.
"The Taliban regularly consulted with Al-Qaeda during negotiations with the United States and offered guarantees that it would honour their historical ties. Al-Qaeda has reacted positively to the agreement, with statements from its acolytes celebrating it as a victory for the Taliban's cause and thus for global militancy."
While the possibility of terror groups finding a new fertile breeding ground in Afghanistan is very real, it's highly unlikely Ireland would be high up on the list of targets among western countries, according to security expert Declan Power.
"The Western world is watching and waiting," he said. "There will be elements rubbing their hands thinking 'we're back'. But in the early stages now, I think the Taliban's focus will be on stability."
Mr Power said that countries such as the US and UK would be able to "bite their tongue" if the Taliban introduce a strict regime to keep out terror groups and not allow them to develop.
However, there are doubts over whether they will follow through on this commitment.
"The fear now is that with the Taliban back in power, in time other Islamist extremsists will gravitate towards the country"
Security expert Tom Clonan said the Taliban has a very similar ideological viewpoint to terror groups such as Al-Qaeda and Al-Shabab.
He told RTÉ News: "The fear now is that with the Taliban back in power, in time other Islamist extremists will gravitate towards the country... after the destruction of the caliphate, for example, the leadership of IS was scattered. Now they could have a safe haven."
Both experts pointed to the Irish involvement in Afghanistan in recent decades, where members of the Defence Forces were deployed in the country under the UN-mandated NATO mission - dubbed Operation Enduring Freedom in Afghanistan.
"Ireland was part of that mission from as early as 2002," Mr Clonan said. "The guys that went there made a serious contribution, and very valued by the Americans and the British. But there's no acknowledgement or mention of it here."
Mr Power said that the Defence Forces had a stake in this given its involvement in the country in the past. He said the Defence Forces had always adopted the strategic view that deployment on the ground can help prevent "aggression on your doorstep".
However, he doesn't think events in recent weeks will act as a catalyst for violence targeted at western nations in the short term.
"If we did see a backlash against the west, [Ireland] wouldn't be top of that list," he said.
Covert, not overt, support
International analysts say that, while the links between the Taliban and Al-Qaeda are strong, the former will offer the latter support more discreetly than during their first period in power when they openly embraced the terror group.
After conquering Kabul for the first time in 1996, the Islamic fundamentalist Taliban regime provided Al-Qaeda with a safe haven to operate training camps, even describing its leader Osama bin Laden as a "guest" of the country.
"[The Taliban] don't want to make the same strategic error, which was blind support for Al-Qaeda which cost them power"
But after being overthrown in 2001 in retaliation for the 11 September attacks in the United States, which were planned from Afghanistan, the incoming Taliban authorities in Kabul are expected to take a different approach this time.
"If the Taliban of 2021 are different from those of 2001, it's not because they have moderated their religious obscurantism, but because they don't want to make the same strategic error, which was their blind support for Al-Qaeda which cost them power," said Jean-Pierre Filiu, a jihadism specialist at Sciences Po university in Paris.
Mr Filiu said that he expected the Taliban to again offer safety to bin Laden's successor Ayman al-Zawahiri and others, citing personal links between the two organisations.
The fathers of Sirajuddin Haqqani and Mullah Yaqoob, both senior leaders in the modern-day Taliban, had past links to bin Laden, for instance.
When the Taliban's leader Haibatullah Akhundzada was appointed in 2016 Zawahiri showered him with praise, calling him "the emir of the faithful".
Mr Power said that there is a hope that the higher echelons of the Taliban now are "more intelligent and strategically aware" than before, with an opportunity to "reinvent themselves" to avoid the worst excesses of the regime.
"The immediate threat assessment [to Ireland] would be that it's very unlikely"
"Make no mistake though, it's not going to be a good time for a great many people in Afghanistan going forward," he said.
He said that while Ireland wouldn't be a high priority for terror groups plotting to attack the west, there is the sense Ireland might be a "soft target" compared to other countries.
"Having said that, the immediate threat assessment would be that it's very unlikely," Mr Power said.
If - and it remains an if at this stage - the Taliban facilitate such groups to proliferate again in Afghanistan, then it may be possible that Europe is again targeted by extremists.
"We had some very difficult times in Europe," Mr Clonan added, citing terror attacks in the mid-2010s. "They all happened when IS had its caliphate in Syria and Iraq. When they had territory. When the caliphate was destroyed, they dropped dramatically.
"Now there's potentially a new sanctuary for Islamist extremists. It does raise grave concerns."
Additional reporting: AFP