Editor’s Note: Julian Zelizer is a professor of history and public affairs at Princeton University and a New America fellow. He is the author of “The Fierce Urgency of Now: Lyndon Johnson, Congress, and the Battle for the Great Society” and co-editor of a new book, “Medicare and Medicaid at 50: America’s Entitlement Programs in the Age of Affordable Care.” The opinions expressed in this commentary are solely those of the author.

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Julian Zelizer: Tuesday's debate is first chance to contrast differing stances of Clinton, Sanders, O'Malley and other Democrats

He says questions can reveal key distinctions in how each would approach governing

CNN  — 

On Tuesday, the Democrats will have a chance to tussle on CNN in their first debate, and it’s an important one. It will serve as the beginning of a much longer conversation that Democratic voters are going to have over the next few months about who should run to succeed President Barack Obama and what kind of campaign that candidate should put together.

Julian Zelizer

True, it is difficult to imagine that Hillary Clinton, Bernie Sanders, Martin O’Malley, Jim Webb and Lincoln Chafee will provide the same degree of entertainment that Americans were treated to with Donald Trump at the Republican debates. There are few political candidates who are willing to say the things that The Donald is eager to share.

This debate will likely have a much heavier dose of discussions over policy, especially with Sanders in the mix, since he has little tolerance for political chitchat.

Each candidate has something to prove. Hillary Clinton can use this as an opportunity to move the conversation beyond the never-ending email issue and the questions about whether voters like her personally.

Bernie Sanders will attempt to show that he is a viable national candidate who can win votes from a broad portion of the electorate despite his “democratic socialist” credentials. Martin O’Malley, who has been full of policy proposals in recent weeks, will attempt to gain much-needed attention after being crowded out from any serious news coverage for months. Webb and Chafee have to make themselves known as candidates and to introduce themselves to the nation.

There is a great deal for moderator Anderson Cooper and the panelists to cover, so most likely a huge number of issues won’t even get discussed. But there are some important questions that would help Democrats evaluate the differences, the strategies, and the vision of each candidate in the race.

1. How do you plan to work around a GOP House?

During most campaigns, there are many promises about the grand ideas that a candidate hopes to accomplish once he or she is president.

But the reality is that the White House needs to deal with Congress, and it is pretty clear that after 2016 the situation for a Democratic president may not be much better than it has been for Obama. The House of Representatives will almost certainly be under the control of Republicans and, given the recent events with Speaker John Boehner’s resignation, the GOP conference will be even less willing (as hard as it is to believe) to compromise with Democrats on almost any issue.

So what would these Democrats do? Rather than a quixotic conversation about setting a new tone in Washington and “reaching out” to the other side, the candidates should be pressed to answer what concrete steps they would take to govern in this gridlocked situation.

Would they rely on executive power, as Obama has done toward the end of his term? Would they use brute partisan force and procedural trickery, if there are sufficient numbers to do so in the Senate? Would they find ways to build grass-roots pressure to force some Republicans into action?

2. What will you do about police violence?

Police brutality has emerged as the civil rights issue of our time. The incidents of violence that have flared throughout the year have stimulated one of the most vibrant grass-roots political movements that we have seen in decades. On the 50th anniversary of the march on Selma, the Black Lives Matter movement has mobilized across the nation to protest the kind of racialized police violence that has been so common, an issue that has been a constant problem in cities with large African-American populations.

While all the candidates have made clear – especially after being confronted by activists at rallies – that they will not tolerate his kind of action, police reform should receive much more attention. Each candidate should be asked exactly what steps he or she would take at the federal level to diminish the frequency of these confrontations.

3. How will you reform a broken political system?

Three of the candidates have spoken about the need to reform the political process, with some attention to specific ways in which the campaign finance system can be improved. Clinton has called for reforms to boost smaller donations while O’Malley and Sanders have argued that publicly financed elections are the only way to fundamentally curtail the power of money in politics.

This is an issue that is paramount and should be the subject both of discussion and debate. Democrats are under even more pressure than Republicans to solve this crisis. The distrust of politics that ensues from the corrupting influence of money undercuts support for government, which is at the heart of Democratic politics.

The candidates need to spend some time in the Las Vegas debate outlining what they would do to make the system better and how they envision building support for reforms that usually die on the vine after a president has been elected.

4. How will you address inequality, specifically?

Like government reform, the fight against inequality is the issue that everyone talks about in vague terms. Clinton, Sanders and O’Malley have lined up to promise they will combat the problem of inequality. It has become a standard part of every campaign speech. Democrats warn about the growing divide between the rich and the poor as well as the insecurity of the middle class.

But the problem is what to do about it. The issue only gets worse every year as the sense of security of the middle class erodes.

Economic recovery without a strong middle class will never recreate the sense of security that undergirded the American dream in the 1940s and 1950s. The candidates must be asked to answer what kinds of steps they would take to address these economic divisions.

5. What is the role of government at home?

The Democratic candidates need to outline their ideological vision and demonstrate to voters that they can offer a compelling rationale for their party. Too often, Democrats have run away from the most basic part of their ideology: that the federal government has a role to play in dealing with social and economic problems.

Too many Democrats have had trouble responding to Ronald Reagan’s claim that “government is not the solution to our problem; government is the problem.”

More than any other Democrat in recent years, Obama has been fairly forthcoming in his defense of government. Each candidate for 2016 should be asked to build on past statements by explaining to viewers why he or she believes government can help solve the problems we face and why markets are not always the best option.

Voters should get to hear how these candidates would respond when they are confronted by blistering attacks from the GOP candidate in the fall of 2016 about how markets are always better at solving problems.

6. What happens to the Iran deal?

Now the Iran deal is in place, Democrats should be pressed about how they will handle enforcing the agreement and dealing with Republicans in Congress who insist on tough economic sanctions.

While the basic parameters of the deal are now clear, the candidates should speak to the public about how enforcement will work over the next few years. At the same time they should discuss their strategy for achieving more stability in the entire region.

7. When is the use of military force legitimate?

Obama has worked hard to bring diplomacy back as a central tool of foreign relations. In response to President George W. Bush’s use of force in Afghanistan and Iraq, Obama has argued that the U.S. can do better by working through diplomatic channels along with international alliances. With the Iranian deal, the President has demonstrated how this can be put into effect.

But there are moments when military force is necessary and some Democrats, including Clinton, have at times been at odds with the President. Rather than simply offering a defense of diplomacy, the candidates can spend some time discussing when force should be employed and under what circumstances. This would be a useful discussion for the primaries and the nation.

These are just a few of the questions that would offer a useful basis for discussion and debate when the Democrats meet. If the questioners can keep the conversation focused on these kinds of policy and philosophical issues, we might get the most substantive event possible.

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