But it was mandatory spending for all the past presidents also. The data is consistent from one budget to the next.
Education spending was given a 25% + boost by Bush (and Kennedy) when Reagan held the line at 2-3% or inflation. That was Bush's choice and that is included in "Human Resources".
The two charts show a tremendous slashing of military % of outlays and a huge increase in HR % of outlays. Much of this increase under Bush is there because he wanted it to be there.
The other chart showed how FDR almost eliminated social spending (HR) during WW II. Almost half the budget was taken down to only 2% of budget. So, it can be cut if a president wants it to be cut.