In 1960, the government decided to cancel the Blue Streak missile based on the Chiefs of Staff's conclusion that it was too vulnerable to attack and thus was only useful for a first strike, and decided to purchase the American air-launched Skybolt missile instead. Macmillan met with Eisenhower in March 1960, and secured permission to buy Skybolt without strings attached. In return, the Americans were given permission to base the US Navy's Polaris-equipped ballistic missile submarines at Holy Loch in Scotland.