it is estimated that there are around 1.7 million birds killed by wind turbines in the US which represents 0.016% of the bird population in the country.
However there are somewhere between 100 million and 1 billion birds killed by flying into glass such as glass skyscrapers every year, no one is sure of exactly how many but the numbers are huge. Plus the fact that those same towers use enormous amounts of concrete, steel, glass, copper, plastics etc much of which is non recyclable and of course given the amount of land in the US there is no real need for them they are more of a prestigious project (such as Trump tower) which the rich and Corporate bodies use to show us mere mortals how rich and powerful they are. At least wind turbines contribute to us all.
By the way, insects aren't nasty they outnumber us by factors of trillions and are some of the most useful creatures on Earth.
If you count the total bird killed by wind turbines that's a very small number, compared to other factors(skyscrapers and cats). Unfortunately if you look at the species of birds in that number the pictures get darker, as mainly big and endangered bird (that have very low reproduction rate) are killed by turbines, birds that cats don't hunt.Sadly the greatest threat to birds are cats, both domestic and feral. Millions of birds are killed by them every year. If you have a cat get it de-clawed immediately. Between cats and glass buildings we have lost over 3 billion birds in N. America in the last 20 years. I am staggered by that number. Even the researchers doing the counts couldn't believe it. We are heading towards a huge wildlife extinction just as fast as we can.