Space stepping stones

Instead of a single strand from earth to orbit you have a series of aerostats (balloons, zeppelins, solar-powered helicopters, morning dew in a jar--whatever) and you link them up only via a series of conveyor magnetic fields which form a mass driver. Please excuse if this is posted here elsewhere! The important thing is that you don't really need one long cable from earth to orbit or half-way, or wherever. You can do it that way, but it seems overly-complicated. You simply need to have the output from power stations that can lift something to the next highest level at staggered intervals. Hanging a transport system from one cable seems a.) like putting your eggs all in one basket and b.) tempting technology and electrical energy transfers by mother earth to deny construction. For that matter, you could hang the last step or two up as an orbital tether within the very uppermost reaches of the atmosphere if you run out of buoyancy in the upper stratosphere. For that matter, if you had a tether like this, as Dagwood points out, you could bypass the whole mess by building a high-altitude dedicated cargo jet to toss along cargo at or near apogee. I guess the idea waz "virtual space elevator" or "disconnected aerial inductrack" using a series of discrete stations as opposed to the more common one-strand unobtainium (ok with nanotubes notquiteyetobtainium) variety.