WASHINGTON — President Trump said Wednesday night that he intends to bomb the Iranian regime “back to the stone ages” for two to three weeks before ending the war — while urging the public to view the conflict as an “investment” for future generations.

“Thanks to the progress we’ve made, I can say tonight that we are on track to complete all of America’s military objectives shortly, very shortly,” Trump said in his 19-minute primetime speech from the Cross Hall of the White House.

“They were the bully of the Middle East, but they’re the bully no longer. This is a true investment in your children and your grandchildren’s future.”

Trump touted the progress already made by the US military while making the case to the nation that he must finish the job once and for all.

“For these terrorists to have nuclear weapons would be an intolerable threat,” he said.

“The most violent and thuggish regime on Earth would be free to carry out their campaigns of terror, coercion, conquest and mass murder from behind a nuclear shield. I will never let that happen.”

Trump argued that Iran’s attacks on neighboring countries and its closure of the Strait of Hormuz to international shipping during the 32-day conflict showed what Tehran’s clerical authorities would have done with a nuclear weapon.

“Americans have been concerned to see the recent rise in gasoline prices here at home,” he said. “The short-term increase has been entirely the result of the Iranian regime launching deranged terror attacks against commercial oil tankers and neighboring countries that have nothing to do with the conflict.

“This is yet more proof that Iran can never be trusted with nuclear weapons,” Trump said.

“They will use them, and they will use them quickly. It would lead to decades of extortion, economic pain and instability — worse than we can ever imagine.

The blistering attack on more than 11,000 targets in Iran, Trump said, has “obliterated” its nuclear program, “blown to pieces” its ballistic missile production sites and “decimated” the country’s hardline leadership.

“Never in the history of warfare has an enemy suffered such clear and devastating large-scale losses. In a matter of weeks, our enemies are losing and America, as it has been for five years under my presidency, is winning — and now winning bigger than ever before.”

Trump said that the war wasn’t quite over — despite keeping to his two-to-three-week timeframe announced Tuesday — warning that the worst is yet to come for Iran if there’s not a deal.

“We’re going to hit them extremely hard,” the president told millions of TV viewers. 

“Over the next two to three weeks, we’re going to bring them back to the stone ages, where they belong. In the meantime, discussions are ongoing.”

“If during this period of time no deal is made, we have our eyes on key targets. If there is no deal, we are going to hit each and every one of their electric generating plants very hard and probably simultaneously,” he said.

“We have not hit their oil, even though that’s the easiest target of all, because it would not give them even a small chance of survival or rebuilding. But we could hit it, and it would be gone and there’s not a thing they could do about it.”

Trump made no mention of a land-based assault by US troops — after reportedly being presented with plans that could have sent commandos to retrieve deeply buried uranium or to seize the Kharg Island fuel depot.

“We’re now totally independent of the Middle East, and yet we are there to help. We don’t have to be there. We don’t need their oil. We don’t need anything they have. We’re there to help our allies,” he said.

“We are unstoppable as a military force. The nuclear sites that we obliterated with the B-2 bombers [last June] have been hit so hard that it would take months to get near the nuclear dust, and we have it under intense satellite surveillance and control,” Trump went on.

“If we see them make a move, even a move for it will hit them with missiles, very hard. Again, we have all the cards. They have none.”

Trump urged Americans to recognize that the conflict, which has claimed 13 American lives, is not going to be a lengthy war — after he ran for president three times railing against open-ended interventions.

“It’s very important that we keep this conflict in perspective. American involvement in World War I lasted one year, seven months and five days. World War Two lasted for 3 years, 8 months and 25 days,” he said.

“The Korean War lasted for three years, one month and two days. The Vietnam War lasted for 19 years, five months and 29 days. Iraq went on for eight years, eight months and 28 days. 

“We are in this military operation — so powerful, so brilliant — against one of the most powerful countries for 32 days, and the country has been eviscerated and, essentially, is really no longer a threat.”