The discovery last week of explosive materials in two cargo planes en route from Yemen has once again thrust the issue of Islamic extremism in this fragile Middle Eastern state into the spotlight. The incident follows September’s arrest of the two so called ‘dry-run bombers’ in Amsterdam Schiphol airport. Customs officials had allegedly found knives, boxcutters – the chosen weapon of the 9/11 hijackers – and a mobile phone taped to a medicine bottle in their luggage after they had flown in from Chicago.Both were US citizens of Yemeni origin.

Two months ago the Washington Post reported that CIA sources believe al-Qaeda in the Arabian Peninsula (AQAP) – based in Yemen – now represents a greater threat to the US security than al-Qaeda in Pakistan. This article came just a day after Amnesty International called on Washington to clarify the role of US forces in unlawful extra-judicial killings of al-Qaeda suspects in the country.

Since the attempt by a Yemeni-trained terrorist to destroy a US-bound plane (again at Amsterdam Schiphol airport) last Christmas, there has been a major crackdown in Yemen. An air strike against suspected militants in December killed 41 civilians, including 14 women and 21 children, and a US cruise missile attack in May mistakenly killed a Yemeni government official.

The Amnesty International report expresses concern about unlawful killings, arbitrary arrest, torture, unfair trials and enforced disappearances. It also highlights the way in which the distinction has been blurred between AQAP terrorists and Houthi fighters – separatists who have waged a rebellion against the state since 2004.

The role of the US military in air strikes in Yemen has never been publicly acknowledged, but according to the New York Times the US ‘provided firepower, intelligence and other support’ in raids across the country last December, and ABC News reported that this support has included cruise missile strikes.

Jihadism in Yemen has been fed over the decades by generations of volunteer fighters returning radicalized from conflicts abroad, such as the Afghan war against the Soviets in the 1980s, the invasion of Afghanistan in 2002 and the 2003 invasion of Iraq. But the roots of extremism in the country can be traced back much further. In the 1960s there was a serious conflict between the forces of radical Islamic fundamentalism, centred in Saudi Arabia, and the secular Arab nationalism of Nasser’s Egypt. A proxy war was fought out in northern Yemen. Fearful of losing access to the huge energy resources in the region, Britain and the US supported the Islamic fundamentalists. Now AQAP, led by US-born cleric Anwar al-Awlaki, is thought to be growing is size, and there are concerns that it is strengthening its links with Al Shabab militants in the Horn of Africa.

Whilst extremists in Yemen represent a growing danger to Western countries it is important that this real threat is not used as an excuse to act unlawfully or to breach human rights. If Western countries become complacent or complicit in allowing arbitrary arrest, torture and extra-judicial killings they will lose the moral high ground in the battle against extremist violence.