Does President Obama's Red Line for Syrian Chemical Weapons Only Cover "Civilian Populations"?

    Is President Obama creating some wiggle room on the “red line” for Syria?  Both John Kerry and Chuck Hagel have indicated that the Syrian forces under control of President Assad may have used chemical weapons.  Today, President Obama acknowledged that currently intelligence is being gathered and analyzed to determine if that indeed is the case.  But he framed his remarks and his answers to reporters' questions in such a way that might indicate that the use of chemical weapons would have to violate a yet unstated prohibition in order to be considered crossing the red line.
    The president made an appearance with King Abdullah II of Jordan for bilateral talks, and briefly addressed reporters.

[Y]esterday, some of you saw that I asked my people to brief Congress about the fact that we now have some evidence that chemical weapons have been used on the populations in Syria.  Now, these are preliminary assessments; they’re based on our intelligence gathering.  We have varying degrees of confidence about the actual use, but there are a range of questions around how, when, where these weapons may have been used...

We have to act prudently.  We have to make these assessments deliberately.  But I think all of us, not just in the United States but around the world, recognize how we cannot stand by and permit the systematic use of weapons like chemical weapons on civilian populations...

...knowing that potentially chemical weapons have been used inside of Syria doesn’t tell us when they were used, how they were used...

    What is unclear is what the president intended by "civilian populations."  Does he mean the line has not been crossed if chemical weapons were used on armed militants?  Otherwise, why would it matter “how they were used”?  Is there a distinction between dropping chemical weapons on a neighborhood of private homes and launching them in a battle directly against an active fighting force?  What actually constitutes a "game chang[ing]" use of chemical weapons?

    The president went on to say:

...for the Syrian government to utilize chemical weapons on its people crosses a line that will change my calculus and how the United States approaches these issues...

     Again, "on its people" could mean civilians, or could be interpreted more broadly to mean any Syrian people whether or not they have taken up arms.  Congress will likely be pressing the administration for answers as the credibility of the United States is at stake, not only in Syria, but in North Korea and Iran as well, where other "red lines" have been drawn.  A world already on edge due to North Korea recent saber-rattling and Iran's nuclear ambitions will be anxiously waiting and watching.