Iraq's prime minister sent intelligence officials and New York leaders scrambling Thursday when he said captured foreign fighters who had joined the Islamic State offensive in his country were plotting to attack the New York subway and the Paris Metro.

Hours later, Gov. Andrew Cuomo took a ride on the E train with MTA chairman Thomas Prendergast to Penn Station and said they had no credible reports of any specific threat. Still, they were coordinating with intelligence agencies as everyone sought more information.

"You are going to see a greater police presence than you have before," the governor promised. Just a day before the Iraqi report, Cuomo had announced the specifics of that very visible force.

Later, Mayor Bill de Blasio and Police Commissioner Bill Bratton took a subway ride, too. The mayor told reporters, "There is no immediate, credible threat to our subway system." He said the NYPD will remain on high alert as U.S. intelligence officials work to confirm the alleged threat.

That's all reassuring. And it's always better to be safe than sorry. But in truth, caution has been woven into the public life of the 8.4 million people who live here -- and the hundreds of thousands more who work here every day -- since the morning of Sept. 11, 2001.

The unthinkable suddenly became thinkable then -- and we have become a very different people.

As for this week, it was already more demanding than most -- with the beginning of the United Nations General Assembly and the start of the Jewish high holy days.

The NYPD and other law enforcement agencies have had a heightened presence for days -- with vapor-detecting dogs and backpack searches. It's wise to maintain such measures until they can get a better reading on the threat.

Meanwhile, life goes on. The five-year, $32-billion capital plan the MTA rolled out this week includes $220 million for subway security enhancements, including more cameras and devices that detect intrusion on the tracks. The full MTA plan is underfunded by about $15 billion, but Prendergast said security needs are the top priority.

The new normal continues.