President Trump plainly feels the nation's grief and anger over young Nikolas Cruz's shooting rampage at Marjory Stoneman Douglas HS. The question is: Will he seize the chance to do something about mass shootings?

As classes were ending Wednesday in Parkland, Fla., Cruz walked into the school that had expelled him, tripped a fire alarm . . . and started shooting as teens ran for their lives or hid.

The carnage left 17 dead and 14 more wounded, making it the deadliest school shooting since the 2012 Sandy Hook massacre, which claimed 26 lives, and the third worst after the 2007 attack at Virginia Tech.

And it came just five months after a much older shooter wreaked havoc at a concert in Las Vegas, slaughtering 59 innocent people and injuring hundreds more.

Trump on Thursday spoke to "a nation in grief," promising "every parent, teacher and child who is hurting so badly" that "we are here for you, whatever you need, whatever we can do to ease your pain."

Citing the kids "who were stolen from us," lives of "unlimited potential" lost, the president said, "No child, no teacher should ever be in danger in an American school. No parent should ever have to fear for their sons and daughters when they kiss them goodbye in the morning."

And: "We must actually make [a] difference."

Absolutely, sir. But, sorry, a meeting with governors and state attorneys general to make school safety a top priority isn't remotely enough.

No, you need to get behind some steps that can help rein in these endless nightmares. No, not end them altogether — but at least to limit the toll and reduce the frequency.