Sen. Marco Rubio, R-Fla., called in to Rush Limbaugh‘s radio show today to defend his involvement with a bipartisan group of senators pushing an immigration reform plan that includes a path to citizenship. Rush kicked off the interview by asking Rubio, “Why are we doing this now?”

Rubio replied: “This was going to be an issue. The president outlined that he was going to push on this. The media was going to focus on this. I thought it was critically important that we outline the principals what we are for and what we are about. There’s this false argument on the left that conservatives and Republicans are anti-immigrant and anti-immigration. And we’re not. Never have been. To the contrary we are pro-legal immigration.”

Rubio then brought up the 1986 amnesty bill which he called, “Well intentioned but counter productive.” At that point Rush broke in and noted the the border security promised in the 86 bill never happened. “Same language used today as was being used in 1986,” Rush said. “For you border security is the first and last… if that doesn’t happen none of the rest does right?”

Rubio agreed with Rush, and added: “That is not enough. It has to be a combination. We need border security. We need workplace enforcement. We need a visa tracking system… All three of those things have to happen. And by the way, the language of the bill has not even been drafted yet. These are just principles. And I agree with you this is going to be a challenge. If in fact this bill does not have real triggers in there, or in essence, if there is not real language in this bill that guarantees that nothing else will happen unless these enforcement mechanisms are in place, I won’t support it.”

That is not exactly a ringing endorsement of where the Senate bill is likely headed. Rush then asked Rubio if he was prepared to let the Senate bill fail. Rubio is. “To the point of them not wanting to do the security, look all I can tell you is that that is a big issue for me and that is why I am involved in this process,” Rubio said. “I have no reason to believe it won’t happen, but if it doesn’t then I’ll come back to you and say it didn’t happen. We tried. They put that in the principles. But then they drafted a bill that didn’t do it and I couldn’t support it.”

And that seems to be the big takeaway from Rubio’s appearance. He wanted to be proactive. He wanted to make sure Democrats and the media could not portray all Republicans as anti-immigrant. And he has succeeded in doing that so far. But going forward, it does not look like the Senate bill has much hope. Already, Senate Democrats are watering down the security measures Rubio wants.

Considering the past failure of existing visa tracking and employer verification laws it is hard to see how Rubio could possibly sign off on anything this Democratic Senate will produce.