For your latest update on the immigration-bill kerfuffle, Sen. Rand Paul threw his two cents into the debate over the pace at which the Senate’s consideration of the Gang of Eight’s immigration bill should proceed in a letter to the Senate leaders on Monday, urging that they pump the brakes on the process and take the adequate time to address the related security failures that “enabled two individuals to immigrate to the United States from an area known for being hotbed of Islamic extremism”:

Dear Majority Leader Reid…

I believe that any real comprehensive immigration reform must implement strong national security protections. The facts emerging in the Boston Marathon bombing have exposed a weakness in our current system. If we don’t use this debate as an opportunity to fix flaws in our current system, flaws made even more evident last week, then we will not be doing our jobs.

We should not proceed until we understand the specific failures of our immigration system. Why did the current system allow two individuals to immigrate to the United States from the Chechen Republic in Russia, an area known as a hotbed of Islamic extremism, who then committed acts of terrorism? Were there any safeguards? Could this have been prevented? Does the immigration reform before us address this?

There should be hearings in the Senate Homeland Security and Government Affairs Committee that study the national security aspects of this situation, making sure that our current immigration system gives individuals from high-risk areas of the world heightened scrutiny. …

I respectfully request that the Senate consider the following two conditions as part of the comprehensive immigration reform debate: One, the Senate needs a thorough examination of the facts in Massachusetts to see if legislation is necessary to prevent a similar situation in the future. Two, national security protections must be rolled into comprehensive immigration reform to make sure the federal government does everything it can to prevent immigrants with malicious intent from using our immigration system to gain entry into the United States in order to commit future acts of terror.

That was one of the testy issues du jour in the Senate Judiciary Committee’s hearing on the same today, in which Sen. Grassley took a bit of umbrage at Sen. Schumer’s suggestion that anyone is trying to take advantage of the Boston bombing merely as an “excuse” to deliberately hold up the bill, rather than an honest endeavor to find and fix major problems:

When the bill’s principal sponsor, Sen. Charles Schumer, D-N.Y., at Monday’s Judiciary Committee hearing accused persons whom he did not identify of trying to use the bombing as “an excuse” to delay or stop the consideration of the bill, ranking Republican member Sen. Charles Grassley of Iowa angrily interrupted him by snapping, “I never said that! I never said that!” …

He added, “I think we’re taking advantage of an opportunity – when once in 25 years we deal with immigration – to make sure that every base is covered.”

Grassley had said on Friday that the Boston bombing should prompt Congress to “understand the gaps and loopholes in our immigration system” and to examine “the weaknesses of our system.”

Schumer said Monday – as he did at Friday’s Judiciary Committee hearing – that “if there are things that come up as a result of what happened in Boston that require improvement” in his bill, “let’s add them to the bill.”

In his opening statements in the hearing, Dem Sen. Leahy insisted that the current bill will definitely improve national security and chided the naysayers: “Late last week opponents of comprehensive immigration reform began to exploit the Boston Marathon bombing. I urge restraint in that regard. … The bill before us would serve to strengthen our national security by allowing us to focus our border security and enforcement efforts against those who would do us harm.” To which Sen. Rubio, one of the bill’s authors, replied:

#BostonBombing not excuse 4 inaction on #immigrationreform.But disagree with Sen.Leahy,if it exposed flaws in system we need to know & fix.

— Marco Rubio (@marcorubio) April 22, 2013