President Donald Trump has laid out new details of his ambitious plan to build a “Golden Dome” missile system to protect the United States from foreign attacks, saying it will be complete before he leaves office.

I would love to be able to build a system that actually worked 100 percent of the time,” Sen. Mark Kelly said at POLITICO’s Security Summit, echoing doubt about President Trump’s ambitious Golden Dome initiative.

The White House’s $175-billion plan to protect the U.S. from nuclear annihilation will probably cost much more—and deliver far less—than has been claimed, says nuclear arms expert Jeffrey Lewis