The terror attacks in Boston wrecked plans for a quick Friday hearing on immigration reform and prompted Department of Homeland Security Secretary Janet Napolitano to withdraw from the high-profile hearing.

Her withdrawal denied Republican Sens. Jeff Sessions and Chuck Grassley — both opponents of the pending Senate immigration bill — the chance to chance to speak to public worries about terrorism’s relation to the 844-page bill.

“We’re here trying to understand why these events have occurred … so this hearing is an opportunity to focus on the issues at hand,” said Grassley, the lead Republican on the judiciary panel.

“We’ll have an opportunity when things settle down to question [Napolitano about] all that’s happened in Massachusetts right now,” he continued.

Senators, he suggested, will have to study the pending bill to see if it leaves gaps and loopholes for threats to enter the United Stats: Senators must study “how can [hostile immigrant] individuals evade authorities and plan such attacks on our soil,” Grassley said.

In response, the Democratic chairman, Vermont Sen. Patrick Leahy, sidestepped the politically delicate issue.

Instead, he highlighted the role of immigration in helping farms and the tourism industry in Vermont while also providing a multi-staged amnesty to illegal immigrants and increasing the flow of foreign workers into the Untied States.

The pending Senate bill was drafted by top Democrats, led by Sen. Chuck Schumer, and by four Republicans, including Florida Republican Sen. Marco Rubio.

Immigration activists from both sides also made sure to highlight — or downplay — reports that the two killers were immigrants from Chechnya, not American-born radicals.

“It’s too bad Suspect # 1 won’t be able to be legalized by Marco Rubio, now” read a tweet from Ann Coulter, a prominent conservative opponent of the controversial bill.

The bill’s opponents rushed to disassociate the suspected terrorism-by-immigrants from the immigrants bill.

“Unless you think the U.S. should simply stop issuing green cards, I don’t see what relevance this has to the debate over #immigration reform,” replied Ben Winograd, an immigration lawyer who favors large-scale immigration into the United States.

“Please, opponents of #immigration reform, keep making outlandish statements that will only backfire,” he added.

The bill includes an amnesty for at least 11 million illegal immigrants, and opens up several new channels for blue-collar workers, white-collar workers and workers with college degrees to enter the country.

The channels could boost annual immigration up from today’s 1.1 million mix of immigrants and guest workers, to a 2 million mix of immigrants, guest-workers and company-sponsored immigrant workers.

Instead of Napolitano, the senators heard testimony from Doug Holtz-Eakin, a conservative economist who supports the bill, and Peter Kirsanow, a civil rights lawyer who opposes the bill.

Kirsanow said the bill would further reduce wages and job opportunities for low-skill Americans.

Holtz-Eakin said all American workers, including low-skill workers in service jobs, are already facing competition from workers overseas. “We’re competing with these workers now, wherever they may be,” he said.

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