A bipartisan group of senators voted 56-41 on Thursday afternoon to end U.S. military support for Saudi Arabia in its intervention in the civil war in Yemen. The move served as a rebuke to President Trump and a Saudi regime led by the 33-year-old Saudi Crown Prince Mohammed bin Salman (known as MBS).

The Senate also unanimously passed a separate resolution, sponsored by Senate Foreign Relations Chair Bob Corker, a Republican from Tennessee, that specifically said the Senate “believes Crown Prince Mohammed bin Salman is responsible for the murder of Jamal Khashoggi,” a Saudi dissident and Washington Post columnist.

While the House may take up Corker’s resolution, it’s not expected to vote on the tougher Yemen measure this year, and its prospects for the next Congress are unclear. But Thursday’s vote marked a symbolic yet meaningful step in the effort to hold Saudi Arabia accountable.

For some senators, the vote was about curbing the brutal civil war in Yemen, which has cost countless lives and caused the world's worst humanitarian crisis. For others, it was a rebuke of Saudi Arabia for murdering Khashoggi. Still others are upset that the Trump administration seemed to try to withhold CIA intelligence linking Khashoggi’s death killing to MBS, when it initially declined to allow CIA Director Gina Haspel to brief Congress. She has now spoken to members of both the House and the Senate.

And then there’s Kentucky Republican Sen. Rand Paul, who would like to see Congress reassert its authority over foreign wars as granted in the 1973 War Powers Resolution. U.S. presidents have been deploying troops unilaterally for nearly 20 years through a 9/11-era law, the Authorization for Use of Military Force.

VICE News sat down with Sen. Paul, one of the supporters of the Yemen resolution and a huge critic of both America’s alliance with Saudi Arabia and the president’s failure to consult Congress on the use of the U.S. military abroad.

Here’s part of his conversation with VICE News Tonight Washington Bureau Chief Shawna Thomas. The exchanges have been condensed for space and clarity:

VICE News: Before CIA Director Gina Haspel briefed some of your colleagues, Secretary of State Mike Pompeo and Defense Secretary Jim Mattis were up here. Did they lie to you about the Khashoggi situation?

Rand Paul: You know, even if they lie in a confidential classified hearing, I still couldn't tell you, you know, because it's classified. What I can tell you is that I've been getting the best classified material that I can get in the newspaper. I'm not getting it from hearings. ...The CIA concluded with a high degree of certainty that the crown prince of Saudi Arabia was responsible for killing Khashoggi. Well, I think everybody ought to know that, but in particular, all the Congress should know about it so we can determine what the policy should be.

What do you think of Jared Kushner's relationship with MBS?

I don't really know anything about his relationship with him. What I would say is that our relationship with Saudi Arabia, they have been a friend and an ally in some ways, and yet they need to behave like a friend and an ally. And they need to behave in a civilized way, or they shouldn't get rewards. Arms sales is a reward; it's not a gift, but it is a reward. And we should only give arms or sell arms because that's part of our national security, to someone that we absolutely trust and that is not acting in a barbaric way to their dissidents.

What do you think Congress is going to do with the Yemen resolution?

It will pass, and that is historic because really it's been a long time since Congress has stood up, grabbed their constitutional power and said to a president, "You can't go to war without our permission." In fact, I can't remember it really ever happening that Congress has done this. It is in the Constitution. Congress is supposed to declare war. The president is supposed to follow our direction.

Earlier this year there was a vote on a similar measure that didn’t get through the Senate. What’s changed?

I called for [suspending arms sales to Saudi Arabia] about a year ago. We got about 20 votes. We did it about six months ago with Sen. [Chris] Murphy (D-Conn.) and we got 47 votes. And then the most recent vote was 63. So really the numbers are going up. I think a lot of it is people are horrified by what happened to the dissident Khashoggi and horrified that it could have happened in a country's consulate. Horrified that that country has lied to us. And then there's also those of us who are also horrified by what they're doing in the war in Yemen.

Does it mean something diplomatically to have the Senate say this?

I think some of it’s symbolic, but it's a very loud, large symbol to have one body of Congress vote to say we should no longer be supporting Saudi Arabia in a war. And I think that their government and the royal family will say, "Hmmm, we risk really becoming a pariah in the U.S. We've been allies for so long. Do we really want to have a problem where we can't even buy parts for airplanes?" So I think the Saudis are waking up, and I think there will be a discussion within the royal family.

Do you think the Saudi ambassador to the U.S. ought to be expelled?

I think he ought to be expelled. Absolutely.

And send another prince over?

I can't dictate to them who they send over. They have a royal family. They’re run as a monarchy, a dictatorial monarchy. They are not anything like the United States. So it can't dictate to them who they choose. But I think we can also say that we're not going to reward that kind of behavior. What's going on in Yemen. What's going on with Khashoggi. But also what's been going on for decades. They’ve been playing a game with us. On the surface, they feed us some intelligence. They say they're supportive. They probably are supportive in some ways. But at the same time, they spend hundreds of billions of dollars supporting these religious madrassas that teach hatred of Christians, Jews, and Hindus.

Shouldn’t we be a little bit worried they won't play our game anymore because we do have a strategic relationship with them in the Middle East?

I really don't see much strategic value in them, to tell you the truth.

Do you think you can keep the momentum going past the Christmas break into the new term — even with a Democratic House?

I think some of it depends on the behavior of Saudi Arabia.

Is bombing Yemen and hitting civilians enough of a behavior problem when it doesn't involve killing someone who lived in America?

Killing the dissident Khashoggi, I think, is enough to keep the ball rolling. People are very unhappy, more unhappy than I've seen them in a long time. And I think that there is a very good chance — and just the Democrats taking over the House doesn't make it less likely to happen. May make it more likely to happen. So we'll see if it brings all of us together. Myself on the right and some on the left come together because of the constitutionality of where war should begin.

A lot of your colleagues don't want to take responsibility for saying yes to war or no to war, which is why presidents keep invoking the AUMF. How do you combat that?

Get new colleagues. I think there are some people up here who are influenceable and maybe are coming around to believing the Constitution. Many of the people up here, if you interview them, they'll tell you they don't believe that Congress should have anything to do with war. They call it "the unitary power of the executive," that the executive as commander in chief can do anything they want. They think they can have martial law in the United States. There are people with crazy ideas up here. You can't change that, because these are adults who have had these opinions. The best way is to talk, not only to your colleagues and you try to convince some of them, but really you talk to the public.

I think if you asked the public and you showed the public the utter despair of the small children, the people starving in Yemen, I think the public would side with me. A lot of the public would say, "Where?" and then say, "How much are we spending over there? And it's causing famine?" I think the public would actually be with me.