Since when has the BENEFIT of Health Care insurance become a Madatory requirement?

Years ago some employers offered Health Care Benefits to their employees as a perk, a benefit! Why has it suddenly become accepted as a responsibility of the employer?
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Because most employers know that if you don't offer some type of health insurance.....you won't be keeping your employees very long. They will go work for someone who does provide health insurance. Health insurance is too expensive for most people to afford on their own. Additionally, people with preexisting conditions that can't get insurance on their own can qualify for an employer plan. If the employers did not provide health insurance - the employees would leave.
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