After the 2014 Winter Olympics officially finished without any of the feared militant attacks on the Russian town of Sochi, attention for international security returns now to the broad and diffused threats from terrorists around the world.
The problem is, as usual, no one is quite sure where, when, or how the next attack will occur.
As if to emphasise the unknown nature of the international terror threat, the US Transportation Security Administration temporarily banned all gels and liquids from flights travelling between Russia and the US.
The ban stemmed from a warning based on intelligence that explosives could be carried on board flights disguised in toothpaste tubes.
Officials from the US Department of Homeland Security issued a warning to US and foreign airlines travelling to Russia for the Winter Olympics to stay alert for toothpaste containers which may store ingredients that could be used to construct a bomb while aboard a plane.
The official said that while the US government is not aware of any specific threat regarding toothpaste containers, it regularly shares information on potential threats with foreign and domestic security partners.
While a bomb concealed in a tube of toothpaste might sound like a fear-mongering excuse dreamed up by the authorities to needlessly constrict air travel further than it already is, there is an important history of militants concealing explosive devices to consider.
An evolutionary arms race
After all, the very nature of the cat-and-mouse game between authorities and militants is actually more of an evolutionary arms race.
Many simpler explosive devices are virtually impossible to carry aboard aircraft. During the Cold War, terrorists from ideologies ranging from Marxist Palestinians, Sikhs, North Koreans and anti-Castro Cubans all tried to destroy aircraft as part of their militant goals.
The inherent fragility of an aircraft structure makes them a particularly attractive target.
Also, few things frighten travellers more than the idea their flight might have a bomb aboard. Being stuck inside a long aluminium tube flying thousands of metres above the ground at enormous speeds, coupled with the potential for a bomb exploding on board is nightmarish.
That fear magnifies and spreads to all potential travellers, even if they aren’t on board an aircraft when something goes wrong. We all vicariously feel the fear of the stricken passengers.
This is a goal in itself for any militant wishing to target aircraft. In the theatre of terrorism, exploding a bomb in a plane not only kills the passengers, it discourages millions of potential travellers from flying.
The quick spread of terror around the globe for the price of only a few hundred grams of explosives is an enormously skewed cost-benefit result for a terror organisation.
However, in cases such as this, it is important not to get too caught up in the exact method of disguise around the explosive.
The example of a toothpaste bomb is not a huge leap forward in terrorist capability. The technique has been used before. The very idea of using various forms of explosive and marrying them to everyday objects has a long history.
Terror groups allow a significant amount of time for inventing new ways to pass security measures on all types of transport.
Explosive options are effectively infinite
There are even reports from the US authorities of credible threats regarding underwear, shoes, printer cartridges, and even breast implants being employed by militants for attack purposes.
Explosives also come in a significant number of forms including, solids, powders, gels, liquids, flexible sheets and cords, and plasticised solids which can be hidden in almost any cavity on any object. The options are effectively infinite.
Toothpaste bombs are not new either. This particular combination of explosives with everyday objects was used by anti-Castro Cuban militants in 1976 to bring down an aircraft over the Caribbean Sea, killing over 70 people.
On top of this, tests have also been conducted in Britain by explosives expert Sidney Alford with a plasticised high explosive called RDX. The explosive was mixed with paste in a small tube, similar to a toothpaste tube.
All it took was a heat source to set off the explosion which was shown to be strong enough to breach the fuselage of a standard aircraft.
In light of facts like this, the US Department of Homeland Security decision to ban all liquids and gels on the flights is prudent.
Explosives such as RDX or PETN (pentaerythritol tetranitrate, an odorless, stable, powerful plastic explosive) are very difficult to detect as they have little or no metal content.
Whole-body X-ray scanners can penetrate clothing and pick out concealed items but these machines are still controversial.
Many security personnel still rely more on assessing the demeanour of passengers when selecting for screening than they do on their machines ability to pick them out of a crowd.
Detecting PETN or other plasticised explosives hidden inside body cavities of terrorists with X-ray machines is still very touch and go.
An al-Qaeda-affiliated group in Yemen has already successfully experimented with such methods of concealment in their attacks on Saudi Arabian leadership.
The constraints faced by authorities certainly don’t make passenger screening futile.
Think of it like a long distance race. The distance already travelled refers to all the low-level threats our current countermeasures protect against. Every time authorities foil an attack they learn and implement fixes for the gaps.
While the range of possibilities for a creative terrorist is effectively infinite, it is only infinite in one direction if authorities are vigilant.
Needing to think outside the box
Ultimately, what warnings such as these teach is that the arms race between terror groups and authorities is a never-ending game.
What we can’t allow to happen is let the authorities take the easy route and simply ban items on all flights on the threat of an attack.
Gels and liquids are necessary for some passengers and removing them would deter many from flying, essentially passing the victory on to the militants without them even conducting an attack.
The key will be to get ahead of terror groups by thinking outside the box and anticipating future threats. But this is easier said than done.
The second generation of X-ray scanners currently being trialled is expected to plug some of the existing gaps but authorities have to embrace the mindset of fighting the next war and being proactive rather than always reacting to counter new devices and their makers.
No matter how vigilant the authorities are, there is always the possibility that attackers will penetrate the protective screen and attack aircraft.
In this way, the attack/defense competition resembles penalty shots in the game of football: at some point the ball is going in the back of the net.
The authorities have to be correct every time, while the militants need only be lucky once. That is why authorities across the world take such drastic banning measures each time a threat appears. They can’t be too careful.
And when it comes to convenience weighed against human lives, protection always wins.
Nathan Smith has studied international relations and conflict at Massey University. He blogs at INTEL and Analysis