The quote that gets right to the heart of the matter:
"Once you give immunity, you can't take it away," said a senior law enforcement official familiar with the investigation.
Simply put, this means that the Blackwater guards accused of murdering 17 innocent civilians while driving the wrong way around a traffic circle will almost certainly not be held responsible for their actions, even if they are proved wholly at fault in the matter. Thus far no evidence has been brought forward to support Blackwater's claim that the guards were in a live-fire situation.
Of course, considering that the current administration relieved Scooter Libby of any accountability for destroying Valerie Plame's career, seeks to force Congress to remove accountability for any telecom corporations who helped the White House tap American phone calls since February 2001, and claims that no executive officer is accountable to anyone, including the people who elected them... it's hardly surprising that they'd extend the same blanket of immunity to their buddies at Blackwater.
Meanwhile the Iraqi government have tried- and failed- to expel Blackwater from their country. The US occupation forces simply ignored them. Prime Minister al-Maliki is going to try again, passing legislation to order the US State Department to replace Blackwater with some other security service... but more than likely that will go nowhere, too, and Blackwater will remain in place, growing fatter and fatter on taxpayer dollars, well into the next administration or even beyond.
Again I say it: the only cure is impeachment, and the American people are long past ready for it. Democrats, if you do not want to see your base disintegrate as the Republican base is doing, take action NOW.