Newsday on immigration policy and American ideals:

The twin forces of immigration and migration have become increasingly vexing problems for the United States and much of the world.

Those tensions were sketched in sharp relief this week across the metropolitan area, where law enforcement officials are working to learn more about the suspect in the Chelsea and New Jersey bombings, a naturalized citizen born in Afghanistan; at the United Nations, where President Barack Obama on Tuesday warned world leaders not to succumb to the belief that people who look different corrupt the character of the countries that welcome them; and on the presidential campaign trail, where contenders have used these events to bolster their candidacies.

It’s been an extraordinary clash of real-life problems and philosophical ideals. And it has made clear that our nation must stay true to the ideals on which it was founded.

That doesn’t mean we should reject outright Republican presidential nominee Donald Trump’s contention that immigration security is national security. It is part of national security, and the long, stringent refugee vetting process has a good track record, but our security apparatus surely can be improved.

The father of Chelsea suspect Ahmad Khan Rahami, for example, apparently alerted law enforcement authorities two years ago about his concerns regarding his son, but the FBI cleared Rahami. Rahami also passed federal screening on return trips from Afghanistan and Pakistan. Separately, an audit by the Department of Homeland Security found that immigration officials mistakenly granted citizenship to 858 immigrants with pending deportation orders; they used different names or dates of birth in applying for citizenship, discrepancies not caught because their fingerprints were not in electronic databases.

The answer is to strengthen our processes, not resort to profiling and bans based on religion. We also must condemn Donald Trump Jr.’s comparison of Syrian refugees to a bowl of Skittles, three of which "would kill you" — a detestable attempt to equate Syrians fleeing death and destruction in their homeland with candy that might be poisoned.

Obama got it right when he pleaded for empathy for such people. He asked all of us to imagine the "unspeakable" happening to our families. The world, he noted, is more secure when we all help those in need.

People have every right to be nervous in these tenuous times, but that must not paralyze us. Obama was correct to decry populism that preys on fear and that longs for a simpler past "free from outside contamination." In a swipe at candidate Trump, Obama said that such a nation which surrounds itself with walls would end up imprisoning itself.

The Journal News on need to stay alert in wake of New York City, New Jersey bombings:

What do you do if you see a bag left unattended, or something else that just looks odd, looks off? After multiple bombs were found — in Seaside Park, N.J., Chelsea in Manhattan and outside an Elizabeth, N.J., train station — law enforcement again reminds people to report suspicious activity.

What does that mean? According to the Department of Homeland Security, focus on the activity or behavior that’s odd — an open door in a facility that’s usually locked up tight; a vehicle where it’s not supposed to be; luggage or a package left unattended; a person whose behavior is unusually focused on security or other aspects of a building or space. Remember that concerns are raised by someone’s behavior, not appearance, dress, race.

If you see something, what next? Call local law enforcement — or 911 in an emergency. Look for law enforcement and report what you see. If you are confused by what you see, and don’t know what it means, call and explain. Local authorities can judge for themselves.

Bombing suspect Ahmad Khan Rahami was tracked to Linden, N.J., after a bar owner who had been viewing news reports saw him sleeping in the bar’s doorway. The bar’s owner reporting Rahami’s presence to police.

Federal, state and city public safety officials said on Monday afternoon that they were not now actively seeking more people in the current terror probe. But that doesn’t mean we must stop being vigilant. The 36,000 members of the NYPD and all law enforcement professionals in and around New York City needed the help of the public.

The 2010 discovery of a bomb in Times Square reminds us that we are experts in our neighborhoods and daily environment, and our observations can make a difference. In that case, street vendors, including Navy vet Duane Jackson of Buchanan, just knew something wasn’t right about a vehicle parked in a no-parking zone. As he approached it, he saw smoke and alerted a police officer, averting a potential disaster.

On Saturday night in Chelsea, a bomb blast injured 29 people; all have been released from the hospital. Earlier that day, a pipe bomb erupted near a Seaside Park charity race; miraculously, no one was hurt. Later that night, a bomb went off outside the NJ Transit station in Elizabeth, and again no one was injured. When Rahami was spotted in Linden, the suspect began shooting, police said. Two Linden police officers were shot, but expected to make full recoveries. The suspect was also shot.

U.S. Attorney Preet Bharara said in New York City on Monday that his office and his New Jersey counterparts will "take a lot of care and a lot of time" to bring accurate charges that can be thoroughly prosecuted.

The specific definition of terrorism includes using violence and intimidation for political gain. Even though the particular motivation behind the weekend attacks remains unclear, officials say these attacks are terrorism.

New Yorkers know what they feel: We are terrorized, we are scared. But we are not intimidated.

As brand-new NYPD Commissioner James P. O’Neill said Monday: "We always have to be in a state of alert." We all have a role in keeping everyone safe, including ourselves and our loved ones.