In briefThe government has said that defence spending will rise to 3 per cent of GDP by 2026.Experts are challenging the government to outline exactly what that will mean in real-world terms.Defence Minister Richard Marles has announced that Australia's defence spending will rise to 3 per cent of GDP, taking the nation's budget allocation for the military to a historic high."We are now seeing the biggest peacetime increase in our defence spending in our nation's history," Marles said while outlining the 2026 National Defence Strategy in a speech at the National Press Club on Thursday.However, the government is facing questions…