At what point will you initiate a go around if you do not receive landing clearance. Runway is clear. Controller otherwise occupied.
Hello sheepless,
In answer to your question, I would personally leave it until I would otherwise have initiated the flare manoeuvre. That may strike some as a little late - but in the situation you have suggested, I think all party's concerned would agree a go-around is in nobody's interests and just means work, stress, and paperwork for everybody.
Before I reached that point of course, I would have tried to get a call in clarifying the lack of landing clearance. Assuming the frequency was blocked - the scenario you hypothesize? - I would meanwhile be re-iterating the go-around procedure with PM, with my finger poised ominously above/behind the G/A trigger switch.