The Obama administration stood up the ACA's core programs in the face of a never-ending shitstorm of Republican defamation, disinformation, noncooperation on the state level, total litigation warfare, and fiscal sabotage. For that they deserve our undying thanks.
By the time Obama left office, the ACA had cut the ranks of the uninsured by about 40 percent, mainly through Medicaid expansion. The marketplace and the expansion proved resilient through the Trump years and provided a vital safety net when the pandemic struck. Since February 2020, Medicaid enrollment by those rendered eligible by the expansion has increased by about 5 million, and marketplace enrollment (with a large push by the Biden administration) by close to two million.
In administering the ACA, however, the Obama administration operated under self-imposed restraints. Pre-Trump, and before Republicans passed their $2 trillion tax giveaway to the wealthy in 2017, Democrats had yet to recognize -- or rather, acknowledge -- the full extent of Republicans' economic fraudulence. Without new appropriations by Congress that they knew would not be forthcoming, Obama and administration officials were reluctant to increase spending on ACA programs and so increase the deficit. They declined to take several measures that would make coverage more affordable or credible. These included the following.

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