I would certainly want to avoid force. Then we would just end up with a bunch of disgruntled players with inside information. This would essentially be a recruitment of all the players truly interested in joining, assuming they fit what we're looking for.
They will, of course, go through boot camp!
The Source
p.s. That is my opinion for absorbing existing alliances. When it comes to just getting a NAP, sometimes pounding it out of them is the way to go.