I see a set of con­straints fac­ing us in the future, and they’re all going to be very expen­sive. First is fund­ing retire­ments for the Baby Boom gen­er­a­tion. Second is con­tin­u­ing increas­es in the costs of health­care. The third is replac­ing decay­ing infra­struc­ture. The fourth is adapt­ing to cli­mate change and repair­ing envi­ron­men­tal dam­age. The fifth is devel­op­ing new sources of ener­gy. The sixth is what I see as in all like­li­hood con­tin­u­ing high mil­i­tary costs. The sev­enth is the costs of innovation.