Kentucky Sen. Rand Paul called for an end of “sanctuary city” policies after a Mexican illegal immigrant, shielded by city authorities from deportation, allegedly shot and killed 32-year-old Kathryn Steinle on Pier 14 in San Francisco.

As CNN notes, there is no strict legal definition of a “sanctuary city,” a term that advocates for mass immigration dislike for its revealing nature. The movement began thanks to American churches in the 1980s who welcomed illegal aliens from Central America purportedly fleeing violence from the Third World, much as they do today. Now, more than 200 state and local jurisdictions defy federal immigration law by refusing to detain illegal aliens who are usually caught in the commission of another crime for deportation.

“Conservatives say we believe in the rule of law, and the beginning of the rule of law is enforcing the law. Since 1986, there was a promise we would enforce the law on border security. We’ve done squat. We’ve done nothing… Eleven million people have crossed over illegally,” Paul said on the Laura Ingraham show on Tuesday. “So, the first thing we have to do is enforce the law.” He added:

But we have not had a president, Republican or Democrat, who is willing to enforce immigration law. Now we have whole cities and states who stand up and say, ‘We just don’t care. We want these people here at all costs, and we’re not going to do anything about it.’ And I think the time’s come for that to end. But it’s not going to end until you have an executive in the White House who says, ‘I will enforce immigration laws.’

Ingraham noted that Americans are not safe from criminal aliens anywhere in the country, thanks to the sheer number who are here illegally. Paul agreed, calling for a grassroots uprising against President Obama and his administration’s dismantling of immigration law:

Well, it goes to the heart of the matter, because like I say, we’ve been promised this over and over again, and no one’s enforcing the laws. The laws on the books say we should have a secure border, and we don’t. Now, could we update the security? Yes. But even the existing laws need to be enforced, and they’re not being enforced. And they’re being flouted and basically laughed at by cities like San Francisco… They’re ought to be a revolution of folks saying, ‘We want you to obey the law,’ and making sure the president hears them loud and clear.

Paul now joins candidates Donald Trump and Texas Sen. Ted Cruz in calling for strict border controls to protect Americans from convicted felons such as Francisco Sanchez, who was deported five times yet sought out San Francisco deliberately because he knew he would not be deported from there — no matter what previous offenses he had committed on U.S. soil.

His stance also puts him significantly at odds with Florida Sen. Marco Rubio. Rubio played a pivotal role in pushing the Gang of Eight bill in 2013. An amended version of Rubio’s bill would have made it impossible to punish sanctuary cities that harbor dangerous illegal aliens like Sanchez by stripping federal funds from them. Had Gang of Eight become law, San Francisco would continue to receive blood money in the form of State Criminal Alien Assistance Program (SCAAP) payments, and U.S. Immigration and Customs Enforcement (ICE) would have struggled to even detain criminals like Sanchez.

Email Katie at kmchugh@breitbart.com.