The political war over President Obama’s controversial policy changes on deportation escalated Friday as the White House pledged to forcefully sell the overhauls to the American people, while many Republicans vowed to derail his efforts.

Obama went to Nevada on Friday to begin what the White House described as a “very aggressive” effort to promote the changes but also to chide his Republican critics for opposing immigration reform.

“We’re not a nation that kicks out strivers and dreamers who want to earn their piece of the American dream,” Obama said. “We didn’t raise the Statue of Liberty with her back to the world. We did it with her light shining.”

Back in Washington, Republicans were launching their own assaults, promising to turn back the immigration effort.

“We’re working with our members and looking at the options available to us,” said House Speaker John Boehner, R-Ohio, “but I will say to you the House will, in fact, act.”

Obama launched his own persuasion campaign at a high school in Las Vegas, where he issued a call for immigration reform shortly after the start of his second term.

“Nearly two years ago, I came here, Del Sol High School, right in this gymnasium … and I said that the time had come for Congress to fix our broken immigration system,” he said. Obama argued that lack of action by the Republican-led House is what forced his hand on taking unilateral action.

“The fact that a year and a half has gone by means that time has been wasted,” Obama said.

Earlier on Friday, White House senior adviser Dan Pfeiffer said that the president’s Las Vegas appearance should be read as the start of a “very aggressive sales job” on behalf of his policy changes.

The president will also make his case on weekend television in an interview on ABC’s “This Week” and in a Chicago address Tuesday. The White House’s sales job will include presidential speeches, interviews and appearances by Cabinet officials.

Pfeiffer said Obama would challenge critics of his executive action to pass legislation permanently reforming the immigration system, while at the same time making the moral case of deferring the deportations of millions of undocumented parents of U.S. citizens and legal permanent residents.

“There’s no reward for the meek here,” Pfeiffer said.

The Republican response to Obama was anything but meek.

Sen. Jeff Sessions, R-Alabama, a leading opponent of the president’s action and the likely incoming chairman of the budget committee, accused Obama of refusing to enforce the law and promised to use budgetary measures to prevent funding for the implementation of the new immigration rules.

Speaking Friday at the Heritage Foundation, Sessions said such action was necessary because Obama “granted amnesty to 5 million people, and he did it by basically saying, ‘I’m not going to enforce the laws of the United States of America.’

“He ignored the interests of the American people, the American workers, recent immigrants who have been here and are looking for jobs in a time of unemployment. He undermined, in my view, the moral integrity of immigration law. And even the constitutional separation of powers. You have to have integrity and consistency in law enforcement if you want to be able to defend what you have done.”

Sessions dismissed the immigration reform bill the Senate passed last year, saying: “Politicians will pass anything that sounds good about immigration as long as it doesn’t change anything, as long as it won’t work.”

But there are those in the Republican Party who worry that the anger may be playing into the president’s hands.

Sen. Jeff Flake, R-Arizona, said in an interview Friday that a growing group of Senate Republicans is coalescing around a more tempered rebuttal to the president: passing a series of standalone immigration bills in the coming months and demonstrating to voters that the party can govern.

“Put legislation on the president’s desk,” Flake said. “We could do bills on border security, interior enforcement, mandatory E-Verify, and address high-tech workers and guest workers.”

Boehner declined to spell out exactly how Republicans would counter the immigration executive actions, which extend protections to roughly 4 million undocumented parents of legal U.S. citizens and young immigrants brought here illegally when they were children.

Obama essentially blamed Boehner for not allowing an immigration bill to come to the House floor.

“I cajoled and I called and I met. I told John Boehner, I’ll wash your car, I’ll walk your dog – whatever you need to do, just call the bill. That’s how democracy is supposed to work. And if the votes hadn’t been there, then we would have had to start over. But at least give it a shot – and he didn’t do it.”

A Boehner spokesman said that the speaker does not have a dog.