Two weeks ago, Senator Marco Rubio (R-FL) gave an impassioned speech about Cuba and Venezuela on the Senate floor. This was his response to a floor speech by Senator Tom Harkin (D-IA), who had recently visited Castro’s Cuba and predictably came back with rave reviews of the Potemkin village.

Rubio dismantled Harkin’s rosy assessment of the hemisphere’s longest-running and bloodiest dictatorship. Many observers described it as Rubio’s finest demonstration of his oratory skills, and a speech that might put him back in the good graces of the conservative Republican base.

Marco Rubio has touched the third rail of conservative politics — immigration reform. He was the most visible of a group of Republicans that attempted to forge a compromise to help solve the problem of the estimated 12 million illegal aliens living within our borders. The issue is so toxic within the Republican Party that many simply wrote Rubio off despite the fact that the initiative didn’t go anywhere.

I never thought I’d see the day when a Republican would have to rehabilitate his conservative image after committing the sin of agreeing with the likes of Jack Kemp, Bill Kristol, Lawrence Kudlow, and Steve Forbes, not to mention Ronald Reagan. But that day has indeed arrived, much to my befuddlement.

The first time I saw Marco Rubio speak, it was in 2007 at a town hall meeting in Miami’s Coconut Grove neighborhood. At the time, he was Florida’s House speaker. His topic was reforming Florida’s backward property tax laws; Rubio was for scrapping the property tax on residences altogether. I remember thinking that Rubio had the right idea — and a gift for communicating why it was the right idea. I began blogging about and supporting Rubio. He did get House passage of his property tax proposal, however it was a no-go in the Senate. But he was making the right kind of waves.

In May 2008, Rubio upstaged the eventual Democratic nominee for president, Senator Barack Obama, at a Cuban American National Foundation luncheon with a rousing speech. He proclaimed: “There’s no statute of limitation on freedom.”

Even as speaker of the state House of Representatives, Rubio’s profile was relatively low. When he decided to throw his hat into the ring for Florida’s vacant Senate seat in 2010 — challenging the then-popular Republican Governor Charlie Crist — many observers thought his campaign was dead on arrival. But Rubio ran a brilliant insurgent campaign, and by the time all was said and done Crist had self-immolated and was without a job. Rubio had ridden the Tea Party wave into the U.S. Senate, and chased Crist from the Party in the process. When Floridians next cast their gaze on Charlie Crist, he was chasing ambulances.

I was fortunate enough to be Senator Rubio’s guest in the Senate gallery for his maiden speech. On that occasion, Rubio outlined his vision for a second American century, a vision that presented a stark contrast to Obama’s vision. Rubio’s star was still rising.

In 2012, Rubio was given a prime speaking spot at the Republican convention. In February 2013, Rubio gave the Republican response to President Obama’s State of the Union speech (and took the gulp heard round the world). As ridiculous as “the Poland Spring Affair” was, it coincided with the beginning of Rubio’s slide into disfavor. His substantive trouble came as he took it upon himself to outline what he labeled “conservative” principles for immigration reform. Initially there was some enthusiasm for his ideas, but as the year wore on and a bill came closer to reality, vocal conservatives intensified their rhetoric, labeling Rubio a traitor for having betrayed conservatism itself.

I was puzzled and a little angry about the reaction among some conservatives, with whom I see eye-to-eye on virtually everything.

I had been advocating for immigration reform for years, trying to allay fears and dispel myths about the largely Hispanic illegal aliens living in America. It’s not that I have a soft spot for these law-breakers (as we’re always reminded, never mind that entering the country illegally is classified as an administrative violation), it’s that I see immigration as an economic issue, and my supply-side economics background gives me a more libertarian view of it. Reason makes the libertarian argument for immigration reform brilliantly.