MANCHESTER, N.H. — Donald Trump vowed swift and aggressive action, if elected, to stem the threat of Islamic radicalism, delivering a policy speech Monday that reflected on the mass shooting in Orlando and painted him as a defender of American values and LGBT communities.

The presumptive GOP presidential candidate reiterated calls he has previously made for Muslims to be stopped at the border and said the United States remains susceptible to still more terror-related violence as long as it continues its “dysfunctional” immigration system.

“If we don’t get tough, and we don’t get smart — and fast — we’re not going to have our country anymore,” Trump said at Saint Anselm College’s New Hampshire Institute of Politics. “There will be nothing — absolutely nothing — left.”

He repeatedly attacked his likely Democratic rival for the White House, Hillary Clinton, and President Barack Obama as too politically correct to prioritize the safety and security of the United States over the needs of foreign countries. Trump said he wants Obama to release the immigration histories of those implicated in terrorist attacks on American soil since 9/11.

The developer and former reality TV star spoke for more than 30 minutes with the aid of the TelePrompTer. Local New Hampshire lawmakers, veterans and former U.S. Sen. Scott Brown (R-Mass.) were among those in the invitation-only audience.

To bolster his case against the current immigration system, Trump cited holes in visa and political asylum policies that he said enabled the people behind the 9/11 terror attacks, the 2013 Boston Marathon bombings and the 2015 shooting in San Bernardino, California.

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The gunman implicated in the shooting early Sunday at a gay nightclub in Orlando was born and raised in the United States.

“The bottom line is that the only reason the killer was in America in the first place, is because we allowed his family to come here,” Trump said, refusing to use the suspect’s name.

The candidate said he was the “better friend” to women and the LGBT community than Clinton, because he is willing to protect them from the terrorists who hate them.

“Who is really the friend of women and the LGBT community?” he asked. “Donald Trump with actions or Hillary Clinton with her words? I will tell you who the better friend is.”

Trump said the Orlando shooting was “an assault on the ability of free people to live their lives, love who they want and express their identity.”

The Manhattan-based businessman has said he believes people should be able to use bathrooms consistent with their gender identity, but has not expressed open support for same-sex marriage.

Trump also called on Muslim-Americans to turn in members of their community that they suspect of terror links, saying radical Islam isn’t compatible with “Western values and institutions” because it is “anti-woman, anti-gay and anti-American.”

Trump previously had planned to deliver a speech to make the case for why Clinton should not serve as president, but he switched topics and canceled a rally planned for later Monday in Portsmouth, New Hampshire, after the Orlando shooting.

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Brown told reporters afterward that he agreed with Trump that even American-born people who are radicalized abroad and “clearly has left their citizenship at the door” should not slip through the cracks.

Gregory T. Angelo, president of the Log Cabin Republicans, which advocates for LGBT rights, called Trump “the most pro-LGBT Republican nominee in history,” but acknowledged the candidate faces potential political risk as he seeks the support of evangelical Christians.