No, actually there ARE possible Medicare cuts coming, if the new tax law is found not to be revenue-neutral - which just about every single analyst, including conservative experts as well as the CBO, has agreed that it will add to the deficit, not reduce it - then mandatory cuts must occur:
From TheHill.com, Nov 14, 2017:
http://thehill.com/policy/finance/budget/360300-tax-bill-could-spur-25-billion-in-medicare-cuts-cbo
(excerpt) The GOP tax bill could trigger automatic cuts worth $136 billion from mandatory spending in 2018,including $25 billion in Medicare cuts, if Congress doesn’t find another way to offset its deficit increases, according to the Congressional Budget Office (CBO).
The tax bill would add an estimated $1.5 trillion to the deficit over a decade. Congressional “pay-as-you-go” rules, called pay-go, require that the White House Office of Management and Budget (OMB) automatically cut mandatory spending if legislation increases the deficit beyond a certain point.
“Without enacting subsequent legislation to either offset that deficit increase, waive the recordation of the bill’s impact on the scorecard, or otherwise mitigate or eliminate the requirements of the [pay-go] law, OMB would be required to issue a sequestration order within 15 days of the end of the session of Congress to reduce spending in fiscal year 2018 by the resultant total of $136 billion,” CBO wrote on Tuesday.
Medicare can only be cut by a maximum of 4 percent through the pay-go rules, however, which amounts to $25 billion in cuts.
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Note the important point: this is re-calculated every year. If the economy grows and tax revenues cover expenditures, entitlements like Social Security and Medicare are exempted from cuts. ONLY if the budget is negative, do the mandatory cuts happen.
Although the budget cuts can come from anywhere, the GOP has already stated its intent to reduce entitlements and have specifically named Medicare in addition to Medicaid:
Ryan says Republicans to target welfare, Medicare, Medicaid spending in 2018
Washington Post, Dec 6, 2017
https://www.washingtonpost.com/news...e-and-social-security/?utm_term=.6d8e6194e89d