U.S. President Donald Trump announced Tuesday that he has chosen a $17.5 billion design for the multilayer golden dome missile defense program, aiming to offset the air threat “even if it is rolled out from space.”

As part of the project, the United States will deploy missile interceptors in space to protect ballistic and supersonic threats.

Here's more about the Golden Dome project.

What did Trump announce?

Trump announced on Tuesday that it would provide $25 billion in initial funding for the project, which would cost $17.5 billion and be completed by the end of the 2029 period.

"Once fully built, the golden dome will be able to intercept missiles even if it is launched from other aspects of the world, even if they are launched from space," Trump said.

“This is very important for the success or even survival of our country.”

Trump also announced that U.S. Space Force General Michael Guetlein will be the main planning manager responsible for overseeing the progress of the project.

"I assure the American people that I will build a cutting-edge missile defense shield to protect our homeland from the threat of foreign missile attacks," Trump said.

Trump also announced: "Canada calls us and they want to be a part of it. So we're going to talk to them."

What is the Golden Dome Project?

Trump said the Golden Dome was designed to dismantle "hypersonic missiles, ballistic missiles and advanced cruise missiles", adding that the plan would have space-based interceptors and sensors.

Pentagon chief Pete Hegseth spoke with Trump that the system is designed to protect “homeland from cruise missiles, ballistic missiles, ultrasonic missiles, drones, whether conventional or nuclear.”

The news came months after January 27, when Trump signed an executive order, “begin immediately to build the most advanced iron dome missile defense shield that will be able to protect the Americans.”

The Iron Dome is Israel's missile defense system that detects incoming rockets, determines their paths and intercepts them. The development of the system is funded by a grant from the United States.

Trump said the existing defense capacity will be used for the construction of the project, with a total estimated cost of about $17.5 billion.

The White House has not released more details about the project. While Trump said the system will be developed in the United States, he has not mentioned which companies will be involved.

From 1981 to 1989, Republican U.S. President Ronald Reagan first envisioned a space-based defense system. During the Cold War, Reagan raised barriers to nuclear weapons, including space technology, as part of his strategic defense program or Star Wars program.

"We will truly complete the work that President Reagan began 40 years ago and end the missile threat to the American homeland forever," Trump said on Tuesday.

Is the Golden Dome Plan feasible?

Industry experts questioned the plan’s schedule and budget.

The funds for the Golden Dome have not been obtained yet. In a press conference Tuesday, Trump confirmed that he is seeking a $25 billion tax bill for the system, which is currently passing a tax bill proposed by Congress, although the amount could be cut in ongoing negotiations.

In addition, the total cost of the project is expected to change. Trump was given three versions of the program, called "medium", "high" and "ultra-high," the Associated Press quoted an unnamed administration official as saying. These versions correspond to the number of satellites, sensors, and interceptors that will be placed in space. The Associated Press reported that Trump chose a "high" version with an initial cost of between $30 billion and $10 billion.

"The new data point is $175 billion, but the question remains, in what time. It could be 10 years," Tom Karako, a senior researcher at the Defense and Security Division of the Center for Strategic and International Studies (CSIS), told Reuters News Agency.

On May 1, 42 Democratic lawmakers in the U.S. Congress signed a letter asking Elon Musk's SpaceX, one of the top technology companies seeking to build a key component of the Golden Dome.

"If Mr. Musk exercises improper influence on the gold dome contract, it would be another example of Mr. Musk's disturbing pattern in the conflict of interest rules," the letter said.

How do China and Russia (the largest competitor in the United States) react?

The United States sees the growing threat from China and Russia, which is its main rival.

Over the past few decades, China has greatly advanced its ballistic and hypersonic missile technology, while Moscow has one of the world's most advanced intercontinental missile systems. Russia and the United States have accumulated the world's largest arsenal of nuclear warheads.

Due to technological advancements, the threat of drones has also developed.

China condemns the Golden Dome as a threat to international security and accuses the United States of prompting an arms race.

"The United States puts its own interests first and is obsessed with seeking its own absolute security, which violates the principle that the security of any country must not come at the expense of others," Foreign Ministry spokesman Mao Ning said in a regular briefing.

"(The plan) increases the risk of space becoming a battlefield, contributes to the arms race, and undermines international security," he said.

The Kremlin said the Golden Dome Missile Shield program is a "sovereign matter" for the United States.

"For the United States, this is a matter of sovereignty," Kremlin spokesman Dmitry Peskov told reporters on Wednesday.

He added: “That’s what all countries do.”

"Of course, the process of events will require the recovery of connections to restore strategic stability in the foreseeable future," he said.