Those deadly gas canisters strike again.
As with their attack, al-Abdaly seems to have either been trained to use gas canisters as part of his makeshift bomb or decided upon using them as obtaining explosives in the necessary quantities for a truly spectacular detonation was just too difficult. The really key connection, as yet unconfirmed and still somewhat disputed in the case of Abdullah, is that both seem to have at least some connection with the self-proclaimed Islamic State of Iraq, the jihadist umbrella group mainly made up of the remnants of what was once al-Qaida in Iraq. The ISI claimed midway through Abdullah's trial that he had been a member and was trained by the group, only for the attack to go wrong due to his incompetence. While they haven't yet claimed responsibility for al-Abdaly's strike, the ISI have released a statement praising him and expressing approval.
Quite why, if al-Abdaly does turn out to have even tenuous connections with the ISI, they seem so set on encouraging the use of gas canisters is difficult to ascertain. While they might make up a part of the bombs used in Iraq, the notion that you can just heat up or pierce gas canisters and the end result will be a deadly explosion is a silly one, as this article from the Register made clear back in 2007. You might, as the footage from Sweden showed, get a somewhat impressive looking fire going and create a fireball which could conceivably hurt or even kill people if you're lucky, or you might, as in London and New York (Faisal Shahzad, hilariously, is charged with attempted use of a "weapon of mass destruction") spark absolutely nothing at all. Either our Islamic extremist friends are getting something very wrong indeed once they're back in the West, or they're being actively trained to fail, as unlikely as that sounds. Jihadist thinking seems to have moved on from cells producing "spectaculars" to individual actions, where even if they fail they're still frightening people and showing that this is a war without apparent end, with the only option being to get the troops home. Conversely, it also means the authorities can keep on intensifying security whilst continuing to justify the lunacy of the war in Afghanistan. Everyone wins, except us.