Defence needs around £100 billion pa extra (has a current deficit of £28 billion) assuming it was spent wisely, double that if recent procurement debacles continue....
Reform of Triple lock would save about £10bn pa
Labours Benefit reforms would save £5bn, Tories plan on cutting £12bn over 4 years from Welfare.
Reform say they would cut £9bn from MH benefits.......
So we get £22billion.... £78bn short....
Getting people to live more healthily would need 'billions spent on things like leisure centres, sport in schools, more sports fields, therapies, loss of taxes from fags booze... re designing cities to get rid of the car and force people on to bicycles.....
Would take decades.
For Russia to invade the UK, it either needs to set sail from the nr Artic or come through Western Europe...atm it cannot even defeat one country after 4 years of trying.... i doubt very much they would take Poland, Germany, France and then cross the channel and march down your High Street.
If we want more spent on Defence, we need to raise taxes one way or another.