The N.Koreans are not suicidal & do not want a war with the USA, S.Korea or Japan.
But the apocalyptic thanatoidal Twelver Shiite Iranians are suicidal, and would fully accept annihilation, if it meant Israel being annihilated too.
The Norks now have a hydrogen bomb, capable of wiping out Israel. The oil-rich Iranians would offer $100 million cash for an A-bomb, and $1 billion for an H bomb.
Israel, existentially, cannot allow this transfer to happen.
The Norks recently threatened Israel militarily directly. For the Israelis, this is an existential causus belli.
Trump will use the Israeli airforce as muscle.
The Israelis will fly 30 ultra long-range F15Is to a US base in the area, or to S.Korea, Japan, India, Taiwan, or even Russia or China or even Muslim Indonesia, to refuel and bomb-up.
They will then take out, 1981 Osirak-style, N.Korea's reactor, leadership, Pyongyang's power station and a WMD factory. The Norks will not be able to retaliate, and if they are seen targeting a Hwasong in Jerusalem's direction, then the US will micronuke its launchpad.
Most of the world will not come down on Israel hard for doing this, and as with Saddam, will be quietly relieved.
N.Korea figures prominently in End Time Torah eschatology.