To the Editor:

Re “Four Key Things You Should Know About Health Care” (Op-Ed, nytimes.com, Sept. 12):

Ezekiel J. Emanuel and Victor R. Fuchs argue that price transparency won’t lower health care costs. Fortunately, they’re wrong, largely because they missed several avenues for how transparency will help.

Transparency should lower prices through four critical paths: better informed patients; better informed employers able to help their workers shop for value; improved ability for employers to discipline middlemen; and public pressure on high-cost providers.

Employers — actually, employees, since all the health care spending comes out of their wages — are paying rates far above hospitals’ marginal costs for providing services.

A panel of federal appeals court judges on Tuesday sounded likely to uphold a lower-court ruling that a central provision of the Affordable Care Act — the requirement that most people have health insurance — is unconstitutional. But it was harder to discern how the court might come down on a much bigger question: whether the rest of the sprawling health law must fall if the insurance mandate does.

Single-payer health care is a dividing line in the race, separating Democrats who want to replace the private insurance system from those who favor improving it. Some candidates — like Bernie Sanders and Michael Bennet — picked a clear side. Others, like Elizabeth Warren and Kamala Harris, took a middle path.

The Department of Veterans Affairs on Thursday will begin allowing a broad section of its nine million enrollees to seek medical care outside of traditional V.A. hospitals, the biggest shift in the American health care system since the passage of the Affordable Care Act nearly a decade ago.

While department officials say they are ready, veterans groups and lawmakers on Capitol Hill have expressed concerns about the V.A., which has been dogged for years by problems with its computer systems. They worry that the department is not fully prepared to begin its new policy, which Congress adopted last year to streamline and expand the way veterans get care.

The Trump administration formally declared its opposition to the entire ACA on Wednesday, arguing in a federal appeals court filing that the signature Obama-era legislation was unconstitutional and should be struck down. The filing was made in a case challenging the law brought by Ken Paxton, the attorney general of Texas, and 17 other Republican-led states. In December, a federal judge from the Northern District of Texas, Reed O’Connor, ruled that the law was unconstitutional.

We don’t know what will emerge as President Trump’s plan to replace Obamacare, which he has promised to unveil immediately after the 2020 elections. But he has recently endorsed several proposals, and they could provide clues. A group of conservative health policy experts has developed a health care proposal that would hand states blocks of money and a few rules, and encourage them to develop their own health care systems. The plan would require that government-subsidized systems offer every American a choice of a private health plan, a requirement that would probably foreclose a liberal state from enacting a single-payer program and that might require restructuring of some state-run Medicaid programs.

A federal judge on Wednesday threw out Medicaid work requirements in two states. In twin rulings, Judge James E. Boasberg of the Federal District Court for the District of Columbia rejected for a second time Kentucky’s attempt to require recipients to work or volunteer as a condition of coverage and blocked a similar rule in Arkansas. Seema Verma, who is in charge of the Medicaid program, said “We will continue to defend our efforts to give states greater flexibility to help low income Americans rise out of poverty.” The ruling will be appealed.

Senate Democrats, including several of the party’s presidential candidates, have savaged President Trump for proposing to reduceMedicare spending by several hundred billion dollars over the next decade.

Senator Kamala Harris of California said the proposed changes in Medicare “would hurt our seniors.”

Senator Elizabeth Warren of Massachusetts tweeted, “The Trump administration wants to cut hundreds of billions of dollars from the #Medicare budget, all while giving billionaires and giant corporations huge tax breaks.”

The Trump administration’s decision to ask a federal appeals court to invalidate the Affordable Care Act has given House Democrats a new opening to pursue what they see as a winning political strategy: moving past talk of impeachment to put kitchen-table issues like health care front and center.

The Democrats’ new bill aims to lower health insurance premiums, strengthen protections for people with pre-existing medical conditions and ban the sale of what Democrats call “junk insurance.”

As House Democrats sit down to draft their vision of governance in the coming weeks, lawmakers find themselves badly divided.

Centrists from swing districts, with the tacit support of Speaker Nancy Pelosi, favor incremental moves to shore up the Affordable Care Act and to lower the out-of-pocket costs of prescription drugs and medical care. They are pushing a variety of measures, such as shutting down cheap, short-term insurance plans that do not cover pre-existing medical conditions and allowing people to buy into Medicare at age 50 or 55.

But they are butting up against an aggressive and expanding group of more than 100 outspoken Democrats — as well as at least four of the party’s presidential candidates — who want to upend the whole system with a single government insurance plan for all Americans — the old concept of single payer, now called Medicare for all.