Mercs and WMDs

Any mercenary unit that commands a starship (esp if ortillery fitted to
support down-well activities) automatically comes under the "controls
WMDs" category. I don't think this is that unlikely. Every little dorky
splinter group that can afford a stardrive can take out a major city if
they are sufficiently PO'd. This is just the nature of life in 2183. I
think the defense grids and controlled space around the Core Worlds must
be something to see. Lots of automated defenses, strict traffic
protocols, and a fair number of CAP fighters and monitors and such to
stop any nutbars. 

I can see the UN or some other nation issuing small WMDs (tactical
weapons) to some trusted mercenary units (as you pointed out, holding
the families is a good hole card) and even some small town-busters (not
outright city busters) to be used at the direction (and only at the
direction) of the national commander. They probably also would provide
some security troops/experts to go with them. Enough to keep the process
above-board and look like the national forces still controlled the
weaponry. 

Plus most mercenary forces would want any release of WMDs documented and
verified 13 ways from sunday so their nuts wouldn't be in the fire
afterwards. Their legal departments would probably demand it as would
any shareholders. 

However, I can see that if the KV and human mercs were fighting on
Asteroid LN-568 with no civs to account for, things could get ugly real
fast....