Not OP, but drone strikes goes on the list.

He campaigned on "change" then governed as a competent manager of the status quo. His first major initiative was to protect Wall Street execs from the crisis they caused and stabilize the banking system on the backs of working Americans.

His crowning achievement was the ACA, which will be a complete economic disaster. It fixed some terrible shortcomings, but it's also been a massive wealth transfer from workers to Wall Street, and the worst is yet to come on that score. He mistakenly gave the health insurance companies a seat at the table as a stakeholder in American healthcare, when they are actually in the financial services business. That philosophical mistake is at the heart of the rapidly accelerating collapse of the system today.

Price controls in the ACA were very badly thought out or, worse, they were well thought out. The rule that requires health insurance companies to spend 80% on healthcare sounds great, but it also means that insurance companies can continue to grow profits out of the 20% by spending more on the 80%. There is a soft cap of 15% on annual rate increases and, sure enough, the industry has aimed to stay just below that. It also means that the insurance companies largely ignores fraudulent claims. Those claims just increase spending on the 80% side, allowing them to increase profits. Anti-fraud enforcement comes from the 20%, which decreases profits. I don't want to write a novel, but I could go on for quite a while on the ACA.

In short, Obama was just another neoliberal who only addressed the worst issues in society when he could sell the solution to Wall Street. The moment he left office he received a flood of cash from the investment community, all under a thin veil of legitimate transactions. He also bankrupted the DNC, setting the stage for Hillary to come in and "rescue" it. The particulars of the resulting takeover led directly to the infamous emails that got leaked and probably threw the election to Trump.

"Looking forward not back"

"Giving the Republicans way more than they should have because that's democracy"