The past few weeks have not been good ones for the CIA. First, the world learned about the US intelligence agency's severe interrogation practices. And now the methods it uses to hunt its targets have come to light. Its internal paper "Best Practices in Counterinsurgency" is something of a guide to "high-value targeting."

"The term 'targeting,'" Germany's left-leaning Süddeutsche Zeitung wrote, "is nothing more than the planned killing of leading rebels, revolutionaries and terrorist bosses."

And indeed, the language in the document is extremely dry. Instead of "enemies" or even "people," it refers to "assets" and "targets." There's no sign of the overly resolute and self-confident rhetoric typical of the period after the attacks of September 11, 2001.

Political scientist Hendrik Hegemann of the Institute for Peace Research and Security Policy at the University of Hamburg says this bland prose was a deliberate choice. Given the high political, economic and human costs of former President George W. Bush's "war on terror," the paper instead concentrates on the more practical matter of achieving the greatest possible efficiency.

"This is presented in a written style typical of specialists that implies they know what they're doing," he said. "The report is meant to convey professionalism. As such, it naturally has a legitimizing function."

Side-effects of the 'war on terror'

Drone attacks have proven only partially effective

Western intelligence agencies are faced with the predicament that the struggle against terror groups such as "Islamic State" may have undesirable side effects. Every attack, Hegemann said, plays into the hands of enemy propagandists.

"Jihadists can argue that the West is illegally killing Muslims," he said. "From this perspective, strategies such as that of the CIA could be doing more harm than good."

In addition, many attempts to eliminate terrorist groups are only partially successful. Most visibly, bystanders are often killed in drone attacks. And instead of "high-value targets," the victims are often low-ranking fighters performing simple tasks who are easy to replace from an organizational and strategic perspective.

In attacks on training camps, usually only lowly recruits die. It is by no means certain that the leadership will be hit. Drone attacks are also always a matter of luck.

The "Islamic State" currently has little problem recruiting new fighters. If they are killed in attacks, the damage to the organization is limited.

Attacks have proven useful fodder for jihadist recruiting efforts

In general, intelligence operations are able to achieve only very short-term success. They can at least weaken the ability of terrorist or jihadist organizations to project force.

But the political problems that helped produce these groups are left untouched. The war against the Taliban in Pakistan and Afghanistan has only been able to keep them at bay for a while. The basic problems - corruption, abuse of power, illegitimate or insufficiently legitimate rule - remain. Any long-term approach must therefore be political.

Is this what we stand for?

The activities of their intelligence agencies ultimately undermine the very political identity of Western countries. Intelligence rely on secrecy - but how far this can go is a question that must be asked. Can spies decide to carry out deadly operations without a court decision? Should they be allowed to use torture? After the recent revelations about the work of the CIA, the agency has come under intense pressure to explain itself.

Hegemann says the CIA was on the verge of turning into a shadow army. "That's why we need to ask whether we want to provide them with a license to kill."

This is a matter of vital ethical and political importance. States whose intelligence services have power over life and death without any judicial control will have a hard time winning the hearts of the people in whose country they operate. And without their support, every military engagement is ultimately doomed to failure.