Important satellite taken out 'by accident'... it's happened already. Doubtless a coincidence
Thus there have been some efforts to fit satellites with subsidiary payloads that might allow them to know if they came under attack, and others intended to endow them with the ability to call home even where no suitable US military ground stations or relay sats are available.

As much detail as anyone's willing to let us see of the SBSS sensor.
The SBSS is supposed to go a step further, by placing a dedicated watcher satellite in a high orbit, able to scan the space above much of an entier hemisphere. The SBSS is equipped with "a digital sensor mounted on a high-speed gimbal", allowing it to quickly get a lock on an interesting spacecraft without needing to swivel the whole craft.
The overwatching SBSS could thus alert its Space Superiority controllers if it saw a foreign spy bird changing orbit for an unexpected run above Groom Lake, for instance. It could also track a potential sat-busting weapon as it snuck up on an unsuspecting, critical US asset: for instance a GPS nav-sat, or - just to pluck a situation from the air - an Iridium commercial comms platform of the sort sometimes so important to spooks, submarines, special-forces troops etc*. Funnily enough an Iridium bird was destroyed in a reportedly accidental collision with an old Russian sat just last year.
"The SBSS is ready to perform its mission in space," says Colonel J R Jordan, vice-commander of the Space Superiority Wing.
Deliberate meddling with another nation's satellites is of course totally forbidden by international agreement. Nonetheless it seems that the US intends to be ready for possible surreptitious violations.
There are even some indications that America might not be above a little bit of unattributable orbital naughtiness itself at some point in the future. ®
*The Iridium satcomms constellation is the only one that can be used without a correctly-oriented dish, ie by a small buoy released from a submarine, or a covert agent or spec-ops detachment far from normal comms facilities. Unsurprisingly Iridium was saved from commercial failure by the US government once it became clear that GSM roaming would be easier for ordinary folk to use.
COMMENTS
Nice to know that our white knight on a horse -
the US Air Force Space Superiority Wing - is there to protect us all from the dastardly bad guys, who might, for example, use their space and satellite capabilites to start illegal wars of aggression in, say, Southwest, Central, and South Asia. The 95 % of the planet's population who don't happen to reside in the US of A are no doubt delirious with joy after hearing this news - just as we were when we first heard of Echelon, etc....
Henri
Actually No, I am not delirious with joy
As difficult as it is to believe from our newspapers which I limit to NYT, I suspect that global corporates including European firms have already developed plans to mine the under sea for minerals.........noticed today internet postings of 'rare minerals in scare supply' which of course would indicate that the ruling powers are claiming the necessity of obtaining these 'minerals.'
Joint US/Canada sea exercise lost 4 of its remotes (7 inches) and sent trained dolphins after them. Naturally satellites would be deployed to replace the aging fleet up there and 'beef up' (how I have come to hate that term) our 'defenses.'
Where are the posts for the disappearance of Saturn's cloud layers and the new visitor McNaught?
Seeing is Believing..... Reading is for Planning and Future Preparation?
The Sublime Alien Satellite Meme .... Rogue Renegade Private Pirate Station Commander gets an outing/airing on this wholly different site too ...and if you are worried about dosh, now would be a good time to cash in your chips and bet on something novel? ........ http://thedailybell.com/1091/Aliens-the-Next-Fear-Based-Meme.html.

Requirements Checklist for Choosing a Cloud Backup and Recovery Service Provider
Cloud based data management
Agentless Backup is Not a Myth
SaaS data loss: The problem you didn’t know you had
What you need to know about cloud backup