I just, for the "fun" of it did a search on Delta.com because I noticed that they have jumped on the surcharge band wagon in February.
Routing DUS-ATL-MSP r/t costs about 230 Euros in "taxes" aka fuel surcharges. If you book it MSP-ATL-MSP it runs you 140 USD. Pretty strange, if you ask me.
It is also masked as "international surcharges". I just call it BS.
What is even worse though is if you try to book an award ticket with FB miles on NW going from the US to Asia. Then you still pay over 240 Euros although NW only charges around 50 USD...