We need a giant Astromatic.
Call Ron Popeil.
It would be a rotating bank of large ginsu-type knives that would slice or dice, resulting in the the now smaller fragments vectoring off their original course and missing the Earth.
Well in a way yes....large 100 foot to 5000 foot diameter guided interplanetary grenades with a heavy nickel/iron base with a pre-stressed metal half dome shell on top.
An appropriate nuke lies inside which is surrounded by an explosion enhancing heavy water shell inside a layer of compressed air or liquid hydrogen and oxygen. The outer shell is studded with heavy rock or metal fragments and the shell itself is prestressed so that it fractures forward under tremendous pressure from the nuke created steam/superheated plasma mix behind it. In a sense a grenade that superheats as well as slices and dices.
What doesn’t get shredded gets melted and even if the object isn’t totaly destroyed...you can bet its direction gets changed especially when far enough out from Earth. The metal base of the grenade if designed right should last long enough to shape the explosion forward.(forward velocity at 20 miles a second should cancel out the reverse effect of the explosion allowing the explosion to be shaped forward) The trick is to find the optimum explosion point, even impact might do major direction change/damage with all that gas/steam/ superheated plasma being released!