Following the resignation of Navy Chief Admiral DK Joshi, who quit on Thursday taking "moral responsibility" over a series of operational incidents of mishaps involving naval warships in the last seven months, isn't it time for Defence Minister AK Antony to step down for alleged inaction and several controversies surrounding him.br br Joshi, who had about 15 months more left in service, submitted his resignation hours after submarine INS Sindhuratna had a mishap in which seven sailors were taken seriously ill and two officers were missing.