It's very strange to me that employees organizing and working together is so controversial, but management doing the same thing is not only expected but we can't even envision anything else.
And reasonable people can quibble about who shoulders more of the blame, but one can't deny that American labor costs were significantly higher than foreign competition and were largely impossible to adjust.
Unions today need better leaders, who realize that the future is in collaborating across national borders with their brethren at all global corporations. The United States simply cannot enforce its own labor laws in China or any other proud nation. Workers created unions themselves, they did not need government to do it for them...which is good because neither the US nor Russia or China rules the whole world.
An employee losing their employer loses ~100% of their revenue until a replacement is found.
The two are nowhere near equivalent.
On the other hand, when employees unionize, a company with 100 employees stands to lose ~100% of their revenue if employees choose to strike. That puts the two sides on an even footing.