The arsenal found in Adam Lanza’s home doesn’t prove that every gun-control proposal should be passed into law. But it does strengthen the case for reasonably tightening firearms regulations.

While the Second Amendment guarantees Americans’ right “to keep and bear arms,” it shouldn’t be interpreted as an open license to accumulate a vast array of military-style weapons.

And it certainly shouldn’t preclude prudent legal restrictions on which guns Americans can possess — and on measures to keep them out of the hands of the mentally ill.

Lanza needed only one of his many guns, a .223 Bushmaster AR-15 semi-automatic rifle, to kill 20 first-graders and six adults in less than five minutes last Dec. 14 at Sandy Hook Elementary School in Newtown, Conn. He then killed himself with a Glock 10 mm handgun.

Search warrant records released Thursday documented that there also were numerous firearms, more than 1,000 rounds of ammunition, samurai swords, knives and a bayonet found in the home where the 20-year-old Lanza lived with his mother, whom he killed before going on his shooting spree at the school.

Police also found violent video games and three photos of a dead person covered in plastic and blood.

And according to Friday’s Hartford Courant, Connecticut State Police spokesman Danny Stebbins told a group of police chiefs two weeks ago that investigators had discovered a large “spreadsheet” with a detailed listing of mass murders, including statistics on how many people were killed and what weapons were used.

The authorities also reported that they recovered three 30-round magazines for the AR-15 from Lanza’s body at the school — and in the same area six more 30-round magazines, three of which were empty.

Connecticut Gov. Dannel Malloy, in a statement released Thursday, rightly cited the heightened risks inherent in high-capacity magazines:

“We knew he used 30-round magazines to do it, and that they allowed him to do maximum damage in a very short period of time. And we now know that he left the lower-capacity magazines at home.”

Also on Thursday, President Barack Obama renewed his call for a ban on assault-weapons sales and a more stringent system of background checks, including extending them to private sales at gun shows.

The clout of the gun lobby still stacks the political deck against such changes.

However, the need for stronger background checks was ominously demonstrated here in Charleston during a Feb. 4 incident. A women was charged with pointing a handgun, which she had purchased legally, at school staffers outside Ashley Hall. She then pulled the trigger several times, according to city police. Fortunately, there was no round in the chamber and nobody was hurt.

That incident moved Sen. Lindsey Graham, R-S.C., to introduce legislation aimed at keeping guns out of the hands of the mentally ill — though he still opposes closing the gun-show loophole.

Tougher gun laws offer no guarantee that mass killers won’t get the weapons they seek to carry out their evil impulses.

But such laws could make those heinous missions more difficult to accomplish.

And as of now, the misplaced zeal for “gun rights” makes it all too easy for the Adam Lanzas of our nation to fulfill their twisted visions.