The US boom and bust has been incredibly damaging to the industry - and not just in the US. During the most recent boom (2005-2008), manufacturers under-invested in production capacity, as they feared (rightly) that demand would not last - this resulted in turbine shortages, price increases across the supply chain, and speculative behavior (financial investors buying rights to tons of turbines in advance and reselling them later). That damaged the price competitively of wind.

And now we have the bust phase, which is killing the same manufacturers on the way down - something now further amplified by the Chinese coming in, as CH noted, with cheap financing in their pockets (something that the US won't do because it's communist or something, and the the UK won't do either, but that Germany has done to a much larger extent than people realize - and smartly so, as it's the cheapest way to bring costs down...)

Wind power