This Thanksgiving, while I give thanks for my Medicare, Speaker Paul Ryan and his Republican Congress are actively plotting to dismantle it.

Medicare is government-provided health insurance for those aged 65 and over, as well as for those with disabilities so serious and permanent that they cannot earn enough to support themselves. Those two groups total more than 55 million of us. Poll after poll shows that those of us who are covered by Medicare love it.

Other industrialized countries have what amounts to Medicare-For-All. Residents of those countries enjoy health care as a matter of right, from cradle to grave. But not here. And those of us who do have Medicare may not have it for long if the Republicans just swept into power have their way.

President Franklin Roosevelt supported universal, government-provided health insurance -- in essence, Medicare-For-All. He established an interagency working group to develop a universal health insurance proposal as part of his Social Security Act of 1935. In the end, though, he feared that those who saw the world the way today's Republicans do, and hated the idea of government providing health insurance, would use the proposal to bring down the entire Social Security bill. So, he did not push it. President Harry S. Truman also supported the idea. He pushed hard for what would have been Medicare-For-All, but never succeeded

Learning from those earlier struggles, the pragmatic President Lyndon Johnson, perhaps the most effective lawmaker of all time, decided to take an incremental approach. His advisers debated whether to start with children, but chose seniors instead. Not only do seniors vote, there was already Social Security, a program designed to provide economic security in old age. Everyone recognized that true economic security did not exist, if retirees were one illness or accident away from bankruptcy. And that concern of bankruptcy was real. Before Medicare, most seniors could not afford health insurance. Those who could, paid three times more than younger people, despite having, on average, half as much income.

So LBJ started with Medicare, expecting Medikids to follow shortly. After that, it would be simply a matter of closing the gap in ages. The initial age of eligibility for Medicare could be gradually lowered from age 65. And the age at which children no longer were covered by Medikids could be gradually increased. And voila! Meet in the middle and we have Medicare-For-All.

But that is not what happened. Just a few years later, President Richard Nixon did expand Medicare to cover people with disabilities. But President Jimmy Carter, who ran as an outsider to Washington, failed to build on the legacy of the New Deal and the Great Society, so no further progress towards Medicare-For-All was made. President Bill Clinton could have proposed building on Medicare's success, but he didn't.

Clinton fought to expand health insurance coverage, but, styling himself a New Dem, implicitly rejected expanding Medicare and instead embraced the Republican ideology of private markets. His proposal mandated that people obtain private health insurance, with the government providing subsidies for those who couldn't afford the costs. Throwing people into the arms of the private health insurance market, no matter how regulated, is at base a Republican idea -- though not one they chose to support. Instead, they united against so-called Hillarycare and helped hand the newly elected President his first major defeat. Complicated to explain and understand, Hillarycare never received the support that expanding Medicare undoubtedly would have. An inferior idea, proposed as a third way, was soundly defeated.

The Affordable Care Act embraced the same basic approach as Hillarycare. Like Hillarycare, Obamacare relies on private markets and competition. Unlike the expansion of Medicare, relying on for-profit health insurers is a flawed, Republican idea. Among its flaws, Obamacare is difficult to explain and understand -- and Republican opponents have taken full advantage of that flaw. Republicans have used opposition to Obamacare to win election after election. Having now won control of both Congress and the White House, Republicans have announced their intention to repeal it.

But today's Republicans are not just threatening to end Obamacare. Ironically, Speaker of the House Paul Ryan is threatening to convert Medicare into Obamacare. He is plotting to end government-provided health insurance and force those with Medicare to buy insurance on the private market, with only subsidies to offset the cost of what the private sector wants to charge. If the Republicans succeed, I and my fellow Medicare policy holders will be on our own, forced to negotiate on our own with for-profit companies, rather than enjoy the protections of our government. Thanks, but no thanks.

Donald Trump ran on a promise NOT to cut Social Security, Medicare or Medicaid.

How ironic! After railing against Obamacare for years, Ryan and his fellow Republicans want to turn Medicare into Obamacare. The Affordable Care Act was better than nothing but far inferior to Medicare. Medicare-For-All is easy to explain, easy to understand, and far superior, in virtually every way, to Obamacare. Despite the fact that Medicare covers those with the greatest health needs -- old people and people with disabilities -- it has lower administrative costs, per capita, than private insurance. We could cover everyone and save money, as a society!

Like Social Security, Medicare is an earned benefit. Everyone -- seniors and people with disabilities who are currently covered by Medicare and workers who are earning that coverage with every paycheck -- must mobilize. This is a real threat. And it is coming now.

This is classic bait-and-switch. Republicans ran on repealing Obamacare. Now they have their crosshairs aimed directly at Medicare. Donald Trump ran on a promise NOT to cut Social Security, Medicare, or Medicaid.

No one who won in 2016 (or for that matter, in any prior election in the nation's history) ran on a platform to dismantle Medicare -- but that is what we are likely to get by Thanksgiving of next year. Indeed, Ryan is threatening action perhaps as soon as January.

Democrats should propose Medicare-For-All as a substitute for Republican plans to repeal Obamacare and destroy Medicare. And all of us should call our members daily to protest Ryan's proposed gutting of our successful and popular Medicare. I urge everyone -- Trump supporters, Clinton supporters, and everyone else -- to join the fight. The message is simple: Keep your hands off our Medicare!

Nancy J. Altman is founding co-director of Social Security Works. Join SSW in telling Donald Trump, Paul Ryan, and Mitch McConnell to keep their hands off the American people's earned Social Security and Medicare benefits.