No, it doesn't.
Because ISIL is AQI. They are an organization literally founded to kill Americans and foment a civil war in Iraq.
Furthermore, we have a pretty good idea of the groups we are actually helping in Syria, as well as a depiction of the groups we helped in Libya, some of whom may now be in Syria. Neither of these sets of groups is ISIL, or ISIL - affiliated.
So, yes. Conspiracy theory. Because in order for it to be true, it would require that secret US foriegn policy was working at odds to US interests, seeking to kill US citizens, and seeking to ruin our stated foreign policy goals in the Middle East. It would require that there actually be a conspiracy to carry out. So yes, a conspiracy theory. Simply saying "Oh, ISIL is a terrorist group. Some of the people we helped in Libya turned into terrorists groups. Obviously a case can be made that the US might have helped any terrorist group" isn't logical, its' nonsensical. I could use the same logic to make the claim that the US supported the Black Panthers, or that Iran was also supporting ISIL. Both of which would be equally idiotic.
I understand that those who have no education in actual terror groups might get easily confused and not know the difference between, for example, Hezbollah and Hamas, or ANF and ISIL. But people who dont' have any idea what they are talking about shouldn't try to propose policy based on their ignorance.
Which takes us right back to where we began. Either Paul is ignorant, or he is lying.