After Rajiv Gandhi THE impression is unmistakable that the political establishment in the country perceives the crisis following the assassination of Rajiv Gandhi to be even more serious than that caused by the death, in similar tragic circumstances, of his mother a little less than seven years ago. If reports, widely publicised in the press, are to be believed, President R Venkataraman himself has considered it necessary to broach with prominent leaders representing different shades of the political spectrum the advisability of forming a national government, putting off the general election already under way and even bringing into being a constituent assembly to rewrite the Constitution and refashion the political system. The all-too-evident signs of panic in high political and government circles have to be explained not so much by the stature of the assassinated leader even as perceived in these circles