When Bernie Sanders struggled during a recent interview with the New York Daily News, the criticisms largely focused on his apparent lack of preparation. It’s not that the senator’s answers were substantively controversial, but rather, Sanders responded to several questions with answers such as, “I don’t know the answer to that,” “Actually I haven’t thought about it a whole lot,” and “You’re asking me a very fair question, and if I had some paper in front of me, I would give you a better answer.”

He ran into similar trouble during a recent interview with the Miami Herald, which asked Sanders about the Cuban Adjustment Act, which establishes the “wet-foot, dry-foot” policy that may be due for a re-evaluation. The senator responded , “I have to tell you that I am not up to date on that issue as I can” be.

The interviews raised questions about his depth of understanding, particularly outside of the issues that make up his core message. Yesterday, making his 42nd Sunday show appearance of 2016, Sanders ran into similar trouble during an interview with CNN’s Dana Bash.

BASH: Let’s talk about something in the news that will be on your plate as a sitting U.S. senator. Saudi Arabia has told the Obama administration that it will sell off hundreds of billions of dollars of American assets if Congress allows the Saudi government to held – to be held responsible in American courts for any role in the 9/11 attacks. How do you intend to vote as a senator? SANDERS: Well, I need more information before I can give you a decision.

Though the senator spoke generally about his concerns regarding Saudi Arabia, t he host pressed further, asking if he supports allowing Americans to hold Saudi Arabia liable in U.S. courts. Sanders replied, “Well, you’re going to hear – you’re asking me to give you a decision about a situation and a piece of legislation that I am not familiar with at this point. And I have got to have more information on that. So, you have got to get some information before you can render, I think, a sensible decision.”

I can appreciate why this may seem like a fairly obscure issue, but the legislation Sanders was asked about was on the front page of the New York Times yesterday morning and the front page of the New York Daily News on Saturday.

It’s not unfair to ask a sitting senator about legislation pending in the Senate that’s quite literally front-page news.

Sanders’ campaign later issued a written statement, clarifying the fact that the senator does, in fact, support the legislation

The broader question, I suppose, is whether a significant number of voters care about developments like these. It’s entirely possible the answer is no. Sanders isn’t sure how best to answer some of these foreign-policy questions that fall outside his wheelhouse, but for the senator’s ardent fans, the questions themselves probably aren’t terribly important. Sanders’ candidacy is focused primarily on income inequality, Wall Street accountability, and opportunities for the middle class, not international affairs.

At a debate last month, the Vermonter conceded he’s a “one-issue” candidate, and for many of his backers, that’s more than enough. It’s not as if Sanders’ support dropped after he made the concession.

But when it comes to building a broader base of support, and demonstrating presidential readiness, these are the kind of avoidable stumbles the Sanders campaign should take steps to correct.

Postscript: Let’s not brush past the significance of the bill itself. The Times’ report from the weekend noted that Saudi officials have threatened to “sell off hundreds of billions of dollars’ worth of American assets held by the kingdom if Congress passes a bill that would allow the Saudi government to be held responsible in American courts for any role in the Sept. 11, 2001, attacks.”

The State Department and the Pentagon have urged Congress not to pass the bill, warning of “diplomatic and economic fallout.” The legislation is nevertheless moving forward – it passed the Senate Judiciary Committee unanimously – and it enjoys support from some of the chamber’s most liberal and most conservative members.