@craigpc As the article describes the case, it's not about hamstringing the right to strike, but rather allowing people who damage equipment to be held liable for that damage.
And this is apparently the pro-union take on the case.
It sounds like the union would be free to strike, they just couldn't damage other people's property and be legally shielded from responsibility for it.
I'd say it might even be better for unions if the public didn't perceive them as having such shield from accountability. It would be better PR, at least, in a time when so many are skeptical of unionization.