Gov. Chris Christie kicked off a four-day tour at the presidential primary starting line by touching the third rail of national politics — entitlements. And his reforms would be radical. Here’s what he proposes: raising the retirement age to 69, thereby postponing eligibility for both Social Security and Medicare to 69; means testing the programs so they’d be available only to seniors who would otherwise fall into poverty. That would mean phasing out Social Security payouts to those with an income of $198,000 a year and eliminating Social Security entirely for people making $318,000 a year. He’d also reform Medicaid.