Bit of a dichotomy.
I'm a life-long Beekeeper. Wasps are incredibly important to the local ecosystem and if at all possible, should be left well alone.
However, wasps can completely destroy a colony of bees in just a few days.
In the autumn, wasps can try to invade a beehive to steal stores (honey). The bees will normally try to defend their colony by killing the wasps but bees can only sting once before they die - wasps have the advantage of having a smooth sting so each wasp can kill many bees.
If enough wasps get into a hive, they can weaken and kill the bees and steal all the winter stores in just a few days - it's a complete frenzy of killing as the bees frantically try to defend the hive and the wasps just kill them. There's a limit to what the beekeeper can do to help - in the Autumn, we narrow the hive entrances so the bees only have to defend about 5cm of opening rather than the 60cm of the whole front of a hive...however, once a few wasps get in, the results can be ferocious and terminal for the colony.
So, for a Beekeeper, wasps are good, but only if they are well away from your hives.
Don't get me started on hornets... (European or Asian!)