Barack Obama will be paid $400,000 for speaking at a conference by investment firm Cantor Fitzgerald.

Former president Barack Obama reemerged this week for his first formal public event since leaving office, but all people can talk about is a future event - specifically, one for which he will be paid his old annual salary for one speech.News broke Monday that Obama would be paid one of those exorbitant speaker's fees that Hillary Clinton received: $400,000 for speaking at a Wall Street conference put on by the investment firm Cantor Fitzgerald.Obama's situation is not the same as Clinton's, in that he cannot run for president again. So taking Wall Street's money, at this point, won't directly affect official U.S. policy that Obama will pursue in the future. Nor is there any rule prohibiting him from receiving the money.But that doesn't mean the arrangement isn't problematic - especially these days and especially for Obama and his party. Below are a few reasons Obama may want to rethink his decision.1. It continues to set a dubious precedentAs mentioned above, there is no rule against Obama doing this. None. But there is the precedent that it sets - or rather, continues to set.George W. Bush and Bill Clinton did this, too, as have Hillary Clinton, Ben Bernanke and Alan Greenspan. And the more that Wall Street firms give out-of-office presidents and big-name politicians these paydays, the more they become the norm. Other presidents will know that such payments are on the table, and it risks coloring their decisions with regard to Wall Street and special interests.Which is already happening with Obama, retroactively. Liberals loved (and miss) his presidency, but if there's one thing the Elizabeth Warren/Bernie Sanders wing is still sore about in the Obama administration, it's the lack of prosecutions for anybody involved in the financial crisis. In September, Warren, a senator from Massachusetts, requested a formal investigation of why no charges were brought.And here's Warren in a 2014 interview with Salon:WARREN: At the same time, picked his economic team and when the going got tough, his economic team picked Wall Street.SALON: You might say "always." Just about every time they had to compromise, they compromised in the direction of Wall Street.WARREN: That's right. They protected Wall Street. Not families who were losing their homes.Whether fair or not, it's not difficult to look at Wall Street paying $400,000 to Obama as a reward for that. In that way, it's tough on both precedent and Obama's presidency.2. We have other rules against retroactively cashing inIt's not as though the idea of holding office and then benefiting from it at a later date is a completely novel one. The Trump administration, the Obama administration and Congress have all instituted lobbying bans on their employees, limiting their ability to lobby government after leaving government - usually for years.These bans aren't written because those aides may one day rejoin government and be influenced by having been made wealthy by certain special interests; they're written because it became so normal for former aides to cash in afterward and basically use their government jobs for a future payday on behalf of well-heeled special interests. The prospect of future wealth became a given.3. Democrats are trying to be the anti-Wall Street partyThis whole thing comes at a somewhat inauspicious time for the Democratic Party: Just as Democrats' true identity is in flux, as Sanders's anti-Wall Street message seems to be ascendant, and as President Donald Trump at times co-opted that message in the 2016 election.That brand of populism clearly has very broad appeal, and now Democrats are being put in the position of deciding whether their former president should take $400,000 from Wall Street for a speech. At the least, it risks suggesting the party's anti-Wall Street posture is in some cases just that - posturing.4. Obama himself discussed the corrupting influence of such arrangements in his bookJonathan Cohn tweeted something Wednesday that I thought was really interesting. There is actually a section in Obama's 2006 book, "The Audacity of Hope," that describes the subtle, corrupting influence of arrangements like this.Here's an excerpt. It's long, but it's worth digesting:I can't assume that the money chase didn't alter me in some ways.Increasingly I found myself spending time with people of means - law firm partners and investment bankers, hedge fund managers and venture capitalists. As a rule, they were smart, interesting people, knowledgeable about public policy, liberal in their politics, expecting nothing more than a hearing of their opinions in exchange for their checks. But they reflected, almost uniformly, the perspectives of their class: the top 1 percent or so of the income scale that can afford to write a $2,000 check to a political candidate.And although my own worldview and theirs corresponded in many ways - I had gone to the same schools, after all, had read the same books, and worried about my kids in many of the same ways - I found myself avoiding certain topics during conversations with them, papering over possible differences, anticipating their expectations. On core issues I was candid; I had no problem telling well-heeled supporters that the tax cuts they'd received from George Bush should be reversed. Whenever I could, I would try to share with them some of the perspectives I was hearing from other portions of the electorate: the legitimate role of faith in politics, say, or the deep cultural meaning of guns in rural parts of the state.Still, I know that as a consequence of my fundraising I became more like the wealthy donors I met, in the very particular sense that I spent more and more of my time above the fray, outside the world of immediate hunger, disappointment, fear, irrationality, and frequent hardship of the other 99 percent of the population - that is, the people that I'd entered public life to serve. And in one fashion or another, I suspect this is true for every senator: The longer you are a senator, the narrower the scope of your interactions. You may fight it, with town hall meetings and listening tours and stops by the old neighborhood. But your schedule dictates that you move in a different orbit from most of the people you represent.And perhaps as the next race approaches, a voice within tells you that you don't want to have to go through all the misery of raising all that money in small increments all over again. You realize that you no longer have the cachet you did as the upstart, the fresh face; you haven't changed Washington, and you've made a lot of people unhappy with difficult votes. The path of least resistance - of fundraisers organized by the special interests, the corporate PACs, and the top lobbying shops - starts to look awfully tempting, and if the opinions of these insiders don't quite jibe with those you once held, you learn to rationalize the changes as a matter of realism, of compromise, of learning the ropes.Obama is talking about politicians who are in office, yes, but he's also talking about how special interests get their hooks in you without you really being conscious of it. He's talking about how taking special-interest money is the easy way out. And that sure seems applicable to today.