No, but they were strikebreaking a fully legal and democratic strike.
They were legally and democratically deciding to go to work. You can't have this both ways - people are entitled to break a strike if they wish. You're absolutely right to point out that for a strike to be effective, it needs to have the support of the vast majority, but it doesn't alter the point that just as people are lawfully allowed to strike, others are lawfully allowed to work during that strike.