The only security threat she posed was to Hu's complacency that he can do whatever he wants to his citizens behind the Bamboo curtain and not face public approbation for it.
The issue here isn't security. It's politics. Or rather, the issue is overarching politics versus common courtesy. I, for one, believe that there is still room, in these hyper-politicized times, for politeness and refinement of behavior. Yes, Bush could have used the heckling incident in some boorish and heavy-handed way to teach his guest a lesson. Bush took a different path and said, "This was unfortunate and I'm sorry this happened." Since both the heckler and President Hu were President Bush's guests, this seems a natural expression of polite regret.
It may be a while before HU returns...but I'm of a mind that if these fools in the administration actually charge this gal with a crime...and convict her...then 50,000 of us ought to march on DC the next time that HU returns to DC...and repeat her words loud enough for everyone to hear...all the way back to Andrews if necessary. The behavior of the administration in this episode, and this funny loss of free speech law....makes the current administration look like fools than conservitives. Seems like we've lost our compass...our map...and our focus in the real world. Surely someone there in the White House grasps what freedom of speech is about...otherwise...they need to find new work.