( CNN ) -- `` Keep the government 's hands off my Medicare . '' Those words -- quoted by so many TV talking heads -- never seem actually to have been spoken by anyone . It 's like that poodle in the microwave story : Everybody has a neighbor who heard it from his cousin . The town hallers were angry , but they were not crazy , and they were not stupid . They knew perfectly well that Medicare is provided by the government . They also knew that their government is proposing to change Medicare in ways they do not like . The health care reform plans backed by President Obama would cut hundreds of billions out of the the growth of Medicare spending over the next 10 years . More ominous for seniors than the dollar figure is the plan behind the number . The president wants to reduce spending on Medicare Advantage , the privately run plans that offer seniors a better deal than conventional Medicare . Over the longer term , the president aspires to shift Medicare patients to teams of health care providers paid by the year , instead of individual doctors charging fees for each particular service -- rather than by the particular medical service they perform . Meet new CNN contributor David Frum . The changes the president has in mind wo n't kill Grandma . But they will change medicine in ways Grandma may find uncomfortable . Ten years from now , Grandma probably wo n't have a personal doctor . Her Medicare will cover less -- and cost more . Medicare was under pressure even before the election of Obama . The gap between the future revenues and future obligations of Medicare and Social Security is estimated by the Social Security trustees at some $ 45 trillion . How much is that ? Adjusting for inflation , it 's the cost of fighting World War II -- 10 times . Medicare is the single biggest spending commitment of the United States . As Obama stacks enormous new health care spending commitments atop the old , Medicare 's already bleak future grows dimmer still . Who wins as Medicare loses ? The short answer is : the uninsured . The president will use the money squeezed from Medicare to extend some form of coverage to the 35 million to 40 million people estimated to lack health insurance . And who are these people ? About one-quarter of them are foreign-born . Recent immigrants to the United States -- unlike the immigrations who arrived between World War II and 1970 -- have tended to be very low-skilled . Their labor is just not worth enough to their employers to support the high cost of an American health insurance plan : $ 13,000 a year , on average , for a family of four . So here 's how the world looks to a Medicare enrollee : . Over the opposition of some 80 percent of the American people , your government allowed millions of poor newcomers to enter the country , many of them illegally . ( Over the past 10 years , half of all immigrants to the United States have arrived illegally . ) These people cut the lawns of your more affluent neighbors , tended their babies , cleared their tables after their restaurant meals . If you were not so affluent , they reduced your wages and crowded your schools , highways and hospital emergency rooms . Now you are being told that your old age will be made less comfortable to accommodate them . Unsurprisingly , you do n't like it . The debate about immigration and health care has centered on whether immigrants who are here illegally might qualify for coverage under the Democrats ' reforms . Theoretically , they will not be eligible , but since Democrats have so far voted against enforcement measures , some illegal immigrants will no doubt slip through . But the debate over illegal immigrants is a proxy for something larger and more unsettling to older Americans . The problem is not illegal immigration , it is all low-skilled immigration , legal and illegal . By importing tens of millions of people who earn too little to pay for their own health insurance , we have made this supremely difficult social problem radically more difficult than it ever needed to be . With `` Obamacare , '' the bill for four decades of permissive immigration has at last come due . Since the 1930s , the United States has run two different kinds of government social programs . One kind of program is sustained by contributions from the very same people who will benefit from the program in future : Social Security , unemployment insurance , workers ' compensation . These programs have never been controversial . The other kind of program taxes some for the benefit of others : Medicaid , social housing , the old welfare programs for the poor . These programs have always been intensely resented . Medicare was the first kind of program : social insurance . Obama 's public option will be the second kind of program : income transfer . That 's the explanation for the resistance the president is encountering . And it 's the emotion that explains the actual quote -- not the bogus quote -- we heard from so many town hall protesters this summer : `` Fix old . No new . '' The opinions expressed in this commentary are solely those of David Frum .
Town hallers know government wants to change Medicare in ways they do n't like , Frum says . He says changes wo n't kill Grandma , but Medicare will cover less and cost more . Changes will benefit the uninsured , some of whom ca n't pay for insurance , he says . Frum : Resistance to Obama 's plan comes because it will be an income transfer program .