http://www.time.com/time/magazine/article/0,9171,1637719-1,00.html
This article has 4 pages, so i'll post only bits in blue in brackets through a summary.
Guinea Bissau is the newest cocaine state in the world. Cocaine use has deflated in usa but is growing up in Europe ("Cocaine use has roughly tripled in Europe over the past decade, while U.S. consumption of the drug has tailed off, according to U.N."). The drug cartels have a problem to solve : geography. It's not easy to ship massive amounts of coke directly towards Europe because of strong security in ports and airports. However, once u've entered, it's easy to move around UE and also it's quite a good business thanks to strong Euro ("A kilogram of uncut cocaine wholesales for about $40,000 in Spain — roughly double the U.S. price. (In Russia and Norway, one kilogram can fetch up to $120,000.").
That's why the drug cartels prefer to ship the drug to Africa ("According to a senior drugs intelligence officer at Interpol, the cartels now export between 200,000 and 300,000 kg a year to West Africa destined for Europe"). Therefore, Guinea Bissau, being the fifth poorest country in the world and on western coast in Africa (not mentioning a lot of small islands with no people) , was perfect to be used as station ("The average person in this country of 1.6 million people earns about $720 a year and dies at 45") : no prisons in the country, policemen have not been paid since january, lack of equipments..., everything is hindering any will of fighting the traffick.
Colombians have started to rent houses in 2004 and corruption is ramping, especially with army protecting the dealers over the police work ("People called and said: 'Here is a plane landing, now they are offloading packets, now the military is coming, the military is loading it and driving toward Bissau,'" a local journalist told me").
Spain is the destination country that is hit the hardest for now, sometimes using the same network than for illegal migrants or the marijuana old route. ("Last year, Spanish police seized 46 tons of cocaine in joint operations with British, Italian and Dutch drug patrols, while Portuguese officials intercepted about 30 tons").
"Seven European governments will open a drug intelligence and operations center in Lisbon later this year. These countries — Spain, Ireland, Britain, the Netherlands, Portugal, Italy and France — will coordinate with U.S. intelligence officers, and plan to begin surveillance flights over the Atlantic in July" but the chances to reduce the traffick are small.