From the Morning Memo:

The ten Democratic candidates on the debate stage Thursday evening sparred for three hours, exposing differences on key issues facing the country — from health care, to immigration and foreign policy. Here are five takeaways from the event.

1. Democrats disagree on health care.

The sharpest distinctions were drawn on this issue which, very broadly speaking, is a debate over how much to expand government-run in the United States to the rest of the country. The debate falls into several buckets: Candidates either want a single-payer system that eliminates private insurance, provide the option of people taking government-backed health insurance to compete with the private sector, or expanding benefits to people when they lose their job or have a qualifying income.

2. What’s the plan for gun control?

All the Democratic candidates agreed they want to do something on gun control in the United States following a series of mass shootings. Those proposals include banning assault-style weapons, strengthening background checks and a red flag law keeping guns away from those deemed to be a danger to themselves or others? But how does that get passed Republicans, who may or may not retain control of one house of Congress after 2020? How does that get through moderate Democratic lawmakers elected in Republican-leaning districts? Polls have shown voters increasingly favor some form of gun control to prevent mass shootings, but the issue remains an emotionally charged one for supporters of gun rights in the U.S.

The SAFE Act, a 2013 measure pushed through by Gov. Andrew Cuomo, required Republican support in the state Senate and was a collection of gun control measures, plus items favored by the Senate GOP. But it remained controversial for the Republicans who supported it at the time and still does.

3. No discussion on abortion.

Surprisingly there was no discussion about abortion and reproductive rights, an issue that once again became inflamed this year following laws restricting it in several states and a measure strengthening it in New York. For such a major issue for Democratic voters, especially women, the omission stood out.

4. Castro’s jab at Biden

Former Housing Secretary Julian Castro suggesting former Vice President Joe Biden had a faulty memory, leaping on him for contradicting himself during the debate, could be seen as a turnoff for many voters. It’s no secret that Biden, 76, is older (as is fellow front-runner, 78-year-old Bernie Sanders). And the concerns over Biden’s age is perhaps real for a party that wants to keep enthusiasm for younger voters. The party historically has done well in presidential races when it nominates a candidate under age 55.

But the Castro jab could also be viewed as an ugly and unfair one, especially by older Democratic voters who tend to turn out to caucuses and primaries.

5. Three hours is… long.

The debate on ABC is a long one. An hour-long debate alone with no breaks can feel like running a marathon. Three hours is a lot of time, but was likely needed in order to give all 10 candidates on the stage some semblance of time to discuss each issue. The supersized length felt a lot like a pre-cell phone, pre-TV age in which people had far better attention spans, helping candidates flesh out positions. But it was also a long debate.