TL;DR
Understanding why US work conditions are so much worse than in Europe starts with understanding the difference between “freedom to” (US) and “freedom from” (Europe).
The US from its inception as break-away colonies was built around the idea of “freedom to.” As in freedom to speak freely, own guns, practice the religion of one's choice or, less harmoniously, freedom to own other human beings, pay the lowest wage possible, create sub-standard work conditions, enjoy more material benefits than tens of millions of your countrymen combined.
The “freedom to” ethos — so immortalized in everything from Clint Eastwood spaghetti westerns to the Marlboro Man to Zane Grey novels to the 1883 / Yellowstone franchises — has been successfully captured and repurposed by America's shareholder class as justification for the shitty work life we all endure. Our oligarch overlords (think Koch brothers) would have us believe all our precious “freedom to” rights disappear the second we venture towards the horrors of socialism. In my home state of West Virginia, folks absolutely believe requiring a living wage, providing health insurance for all, and imposing workplace requirements on the Amazons of the world would all lead to the loss of their “freedom to” agency.
Europe's most cataclysmic events in modern history, in contrast to colonies yanking against their master's leash, were the French Revolution and the Bolshevik Revolution in Russia. These highly violent repudiations of royal tyrannies — which held people in a state of virtual serfdom — set the groundwork for states built around “freedom from.” As in freedom from extreme poverty, freedom from lack of medical care and education, freedom from degrading work conditions, freedom from a world dominated by unfettered capitalism. Europe isn't perfect by any means, but anyone who has lived there for any amount of time can instantly feel the emphasis on “freedom from” creates a society where privation and workplace fear aren't present in the way they are in the US.
IMHO, fixing America starts with breaking the supposed link our shareholder classes have convinced everyone exists — that you can't have personal freedoms without rampant, anything goes dog-eat-dog capitalism. Convince people that you can be free AND lead a dignified life and you'll be on to something very special.