When the historic 2008 election was over, the Democratic party found themselves with:
1. the presidency (Obama)
2. a Senate with 57 Democrats and 2 independents (forming a majority of 59)
3. control of the House by 256 to 178 (a larger margin than the GOP has today)
What did the Democrats do with their overwhelming 2008 mandate?
With an economic crisis underway, a deep recession with an unemployment rate of 8% and growing (to 10% two years later) we got Clintonista retreads Lawrence Summers and Tim Geithner and the Democrats essentially continued the Bush bailouts of the big banks and Wall Street instead of undertaking serious bank restructuring, re-regulation, and implementing a massive infrastructure rebuilding program, all of which would have done more long term good and worked faster, actually restoring a healthier economy than existed before the '08 crash.
Another big item was to follow through on a campaign promise regarding health care. On that one Obama and his party took single-payer (Medicare for all) off the table and gave us a program crafted in a right-wing think tank and piloted in Massachusetts (by a Republican governor named Romney).
In a nutshell, Obama and the Democratic party came in at an FDR moment and instead of changing direction, quickly demonstrated their loyalty to the big money. Then, in the White House Obama chose to be guided by the graceless contributions of Rahm Emanuel (now moved on to becoming the most hated mayor in the history of Chicago). For Secretary of Education we got the genius leadership of Arne (more testing) Duncan who put Bush's No Child Left Behind on steroids. And Hillary Clinton was installed as head of the State Department where she ran it like it was a wing of the Pentagon.
Foreign policy under Obama and Hillary continued to look a lot like the Bush years. By more or less following Bush's timetable for withdrawal, the Democrats could claim fewer "boots on the ground" in Iraq. But military involvement (and remote control killing) expanded all over the region and beyond, giving assorted jihadists in more places a continuing raison d'etre while draining U.S. resources, reducing credibility, and making life miserable for the vast majority of Muslims (and others) in the Middle East and much of Africa. People who, like Americans and people everywhere, aren't that interested in politics or ideologies and want nothing more than to go about the difficult enough job of making a decent life for their families.
Did you ever consider how grim things are when Sarah Palin's line, even if she was just being her snarky self, turns out to be so apt - "How's that hopey, changey thing working out for ya?"