>If, say, Biden had been sworn in as President in an emergency would the rules have allowed him to have a full term?
It would have caused massive unrest.
Biden would have completed the term to 1/20/17. In theory, he could later have two full terms of his own, BUT he would have to wait until at least 2020 to run, since the election had happened already.
Under the False Flag scenario you propose (and remember this was in the throes of the BLM marches) unrest would have set in extremely quickly. It actually IS a good motive and a good theory on your part, as it also would have covered up BHO's involvement in everything else.