SinceenteringDowningStreet, MrJohnsonhassaidthatthebackstoponinsurancepolicyof a temporarycustomsuniontomakesurethereisneverhardborderontheislandofIrelandhastogo.
InhisfourpagelettertoMrTusk, hespoutoutexactlywhyMrJohnsonsaystheBaxterbreakstheGoodFridayagreementhelpeddeliverpeaceinIrelandfor 20 years.
AfterBrexitwiththeletter, theprimeministerwantedtolookasreasonableaspossibletoappearconstructiveinthefaceofwhatheislikelytosayisintransigencebytheYousummonWestminsterthink, however, buthe's layingthegroundfor a blamegameagainstBrussels.
IftheUKendsofleavingtheyouwithout a deal, everythinginthisletterhasessentially, Beansaidbeforeweknowthe U isn't budgingonthebacksupon.
WeknowthatMrJohnsonhimselfwantsitremoved.
TheprimeministerisofftoBerlin, thentoParison, thenbe a Ritzlaterthisweekforthe G sevensummit, hisdebutontheworldstage.
Butgivenhisstanceonthebackstopontheuncompromisingresponsefromthe U number 10 isexpectinganykindofBrexitbreakthrough.
Yes, therewillbesmilesandpleasantries, butthefactisthereisnoprogressonthatdoesnotbodewellfor a smoothBrexitinSeptember.