They said one program would end freedom in America, and worried that another was akin to socialism.
No, we're not talking about aspects of the Affordable Care Act.
If you think politicians are up in arms about the upcoming launch of Obamacare, you must not be old enough to remember the name-calling and dire predictions that predicated the introduction of two other major legislative milestones: Medicare and Social Security.
"There is a history around these government programs of controversy, of fear, of partisan division and ideological debates," said Jonathan Oberlander, a professor of health policy and management at the University of North Carolina.
Of course, both Social Security and Medicare were enacted despite such opposition—and in both cases, experts say they quickly became quite popular and have stayed that way.
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"We've been through this before, and in some ways that's comforting because Medicare and Social Security turned out OK," Oberlander said.
But although the rhetoric around Social Security and Medicare was dire, experts say it was not nearly as venomous as the current fight over Obamacare, which has included an all-night speech replete with references to Nazism and threats of a government shutdown.
"The current debate is an order of magnitude more intense, dishonest and verging on indictable than was the case with either of those programs," said Henry Aaron, a senior fellow in economic studies at the Brookings Institution and an expert on health-care financing.
Experts say Social Security, in the 1930s, and Medicare, in the 1960s, were established at times when the partisan divide between Republicans and Democrats was not nearly as strong as it is today.
In addition, during both periods the Democrats pushing for the programs had a much stronger grip on political power.
"There were some people very strongly opposed to Medicare (and) very strongly opposed to Social Security, but politically they did not have the clout that those opposed to Obamacare, or ACA, have today," said Daniel Beland, a professor of public policy at the University of Saskatchewan in Canada, and an expert on the U.S. Social Security and Medicare systems.
Still, the fears about Social Security and Medicare are surprisingly similar to the ones critics have raised about the Affordable Care Act today.
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The Social Security Act, which in 1935 introduced old-age insurance, unemployment insurance and other social welfare programs, faced critics who worried it would threaten democracy itself.
"Isn't this socialism?" one senator, Thomas Pryor Gore, a Democrat from Oklahoma, asked at one point.
Three decades later, the plan to introduce Medicare also faced foes including the American Medical Association and Republican presidential candidate Barry Goldwater.
Another critic was Ronald Reagan. In 1961, the future president recorded a speech in which painted a dark picture of a time in which doctors would be told by the government which patients they could see, and where.
If his listeners didn't oppose Medicare, he warned, the medical plan would be followed by "other federal programs that will invade every area of freedom as we have known it in this country."
"If you don't do this and if I don't do it, one of these days you and I are going to spend our sunset years telling our children, and our children's children, what it once was like in America when men were free," Reagan added.
Reagan's efforts to thwart Medicare weren't successful, and the conservative lawmaker even ended up being the one to overhaul Social Security while serving as president.
That doesn't mean the Affordable Care Act is assured the same fate. Experts say today's health-care overhaul is more complex than Social Security and Medicare, and it comes at a time when politicians are far more deeply divided.
Rep. Michele Bachmann, Republican of Minnesota, has argued that the health-care overhaul could literally be deadly.
"Let's repeal this failure before it literally kills women, kills children, kills senior citizens. Let's not do that. Let's love people. Let's care about people. Let's repeal it now while we can."
Other critics have said it veers dangerously into socialism.
"How much more socialist can you get than the government telling everybody what they can do, what they can't do, how they can live," Rep. Louie Gohmert, a Republican congressman from Texas and a key Obamacare opponent, told the Huffington Post last year.
Edward Berkowitz, a history professor at George Washington University in Washington, D.C., noted that any major overhaul like this is at its most vulnerable when it is being implemented, and the inevitable glitches need to be sorted out. He noted other examples of ambitious legislation, such as the Medicare Catastrophic Coverage Act in 1988, that didn't end up working out.
Still, others note that one reason both Medicare and Social Security endured is that people quickly started getting benefits, and enjoyed them. Even Ted Cruz, the Texas senator who is among Obamacare's fiercest opponents, told Fox News one worry is that people will become "hooked" on Obama's health-care plan and not want to repeal it.
Beland, the professor, said one risk for proponents of Obamacare is that Americans who are getting a benefit from the program, such as being able to keep an adult child on their health-care plan, may not realize it is because of the health-care overhaul.
"When you receive a Social Security check, you are aware of it," Beland said. "When you deal with indirect measures or regulatory changes, you benefit from government action without knowing that."
Still, if Obamacare can survive the implementation period, some experts say the next generation may find it hard to believe that there ever was a time when the political rancor over the program was so intense.
"If we get by the initial years, people will look back on the rhetoric that is being (used) today with absolute incredulity," said Aaron, of the Brookings Institution.