U.S. President Donald Trump unveiled a plan for his ambitious "Golden Dome" missile defense shield this week, stating it will cost $175 billion and take about three years to develop — but some experts...

Trump announced the $175 billion concept in the Oval Office on Tuesday, saying it would put U.S. weapons in space for the first time and be would be “fully operational” by the end of his term in early...

An initial sum of $25bn (£18.7bn) has been earmarked in a new budget bill - although the government has estimated it will end up costing much more than that over decades.