The railroad contract was a strange case because they were dealing with numerous unions. The vast majority had approved the contract. There were only a few holdouts that got the contract forced on them.
August 1st 330,000 UPS drivers could go on strike. They deliver 24M packages a day that comprises 25% of the packages shipped in the US. It's 6% of the GDP. This is when we'll find out how labor friendly our president is.