geneva u.s. president donald trump risk drive iran towards nuclear proliferation worsen standoff north korea washington end nuclear deal tehran former u.s. secretary state john kerry say late thursday kerry negotiate 2015 deal iran world power speak week trump refuse certify tehran compliance amid grow tensions pyongyang nuclear ballistic missile program want negotiate north korean leader kim jong un goal avoid war try able diplomatic resolution bad thing first threaten destroy country unite nations kerry say speak private lecture deliver geneva graduate institute secondly screw around deal already make message make deal unite state keep word say nuclear deal place iran tough restraints include inspections round-the-clock surveillance track every ounce uranium produce kerry say would notice uptick enrichment like say snap finger nobody know common sense understand virtue accelerate confrontation possibility might decide want break make nuclear bomb instead 10 15 25 years now kerry former senator head u.s. senate foreign relations committee tell swiss media trump leave iranian deal fate congress dangerous open door party politics congress unilaterally renegotiate multilateral accord geneva daily le temps quote say possible congress would make unreasonable decision would put iran supreme leader ayatollah ali khamenei complicate political situation could force retaliate slippery slope khamenei say wednesday tehran would stick accord long signatories respect would shred deal washington pull state tv report iran violate accord u.n. sanction would snap back place kerry tell audience moreover point time folks year break-up time need world able bomb facilities submission end deal could lead iran hide fissile production facilities deep mountain insight scenario trump open say let get rid deal actually proliferation far damage dangerous kerry say end iran nuclear deal would worsen north korea situation kerry