It hits me when I’m not thinking about it, and the tears well.

Eighteen years later and I’ve been to that 16 acres countless times, but I’m still too shaky and raw to go deep underground to the completed 9/11 Memorial & Museum.

Sure, I put on my brave reporter-photographer face and saw the press preview. But back then, the large artifacts were hidden from my psyche.

These were the same bent steel beams, squashed fire engines, antenna pieces and meteorites — sharp rocklike monsters and mini-balls fused in the hellfire — that were stored in the airplane hangar at JFK.

I wasn’t the only one to hear the ghostly murmurs of the lost souls.

I hear the same voices when I visit Gettysburg. Nearby, there are 1,328 monuments and statues of various sizes placed along the winding country roads and edging the hallowed fields where battles once raged — all celebrating our American dead as well as small moments when the fighting stopped so a bird’s nest could be placed back in a tree.

In Gettysburg, 157,000 men and a few disguised women fought bravely over three days with roughly 7,060 killed, 33,260 injured and nearly 10,900 missing.

They weren’t thousands of sitting ducks in an office complex that included two super-tall towers when they were attacked — literally out of the blue — one beautiful morning. Those terrorists using airplanes as missiles killed roughly 3,000 here.

The collapse of the towers showered poisonous ghostly dust on thousands more, many of whom are now gravely ill. Already, 263 first responders have succumbed.

Those at Gettysburg were soldiers fighting a war that tore our country apart.

Yes, the attack on Sept. 11 brought our country together, albeit there was plenty of squabbling later over what would be rebuilt. Since then, a park with leafy oak trees and pools of rushing water, tall and small buildings, stores and the swooping wings of Calatrava’s oval mall make ground zero sparkle with new life.

But now, to quote President Lincoln while speaking at Gettysburg: “We are engaged in a great civil war” and “must highly resolve” that those who are dead “shall not have died in vain.”

I pray now, as Lincoln said, “that this nation, under God, shall have a new birth of freedom and that government of the people, by the people, for the people, shall not perish from the earth.”