How long would the U.S. last against the rest of the world?

We won't last that long. She left out police call, post clean up, ASU inspections, health and welfare inspections, the 12 hours a day 1SG spends yelling at everyone in formation, APFT;s, uniform changes, PT belt changes, SSD's (can't fight without having your SSD's done), mandatory training, pointless training, connex inspections, missing MRE's, Joe coming home to see Jody struck again, red ink NCOERS and OER's, CO, BN, BDE, and DIV runs to nowhere, changes of command that take the entire day to say "all previous orders are still in effect", and the hand off to 1SG who has to make his day complete by yelling some more. SGT's Time, payday activities, being sent to legal, QSP and QMP boards, SFC Snuffy who couldn't find his authorized PT's, so he breaks out the solid grey ones from the 90's that are WAY too short. 0500 formations for a range that isn't going hot until 1000.
All of that is conventional Army...the Warrants are sitting at home with a beer, their issued M4's with more custom SOF crap just chilling in their boxer briefs until the W5 gives the code word, and all hell is released. That's how we would win....only using the warrants.
America's ace in the hole are our dedicated Corps of SPC's. You don't see them...they see you. At the mention of hostilities, they have the keys to the AHA, and have taken all the good stuff first. That 7.62 mm mini gun? They took it too. The hot stripper, they didn't take her, but she damn sure knows who will save her ass. Land invasion? Hundred and worst screaming chickens? What the hell are they saving when damn near everything is in the Stan, and the CO has to circle X whatever is left. 82nd? If you cannot air drop equipment without laughing your nuts off, you're not going anywhere. Besides it's AAW...meaningless runs, more runs, retarded Div picture that you can't see yourself in, and Art15's. LOADS of them. It will come down to two: the BRO, and the CAV (cough.....cough...he said CAV saving someone). Ok it will come down to two: the BRO and TOG. No one can stand for no damn reason longer than the TOG.