We're all dooooomed....
Problem is, Mr B, that the defense budgeteers have no good place to run. Congress spent the 00s competing to raise the pay and benefits of Our Warfighters and thereby landed the Pentagon with massive costs that will inevitably increase. The bills for operations here and there continue to fall due, and most of the combat equipment is old except for Reapers and MRAPs and suchlike that are as much use as a chocolate fireguard anywhere except OEF/OIF scenarios.
It's that, not poor logic, that takes out the B-1. It's too expensive for what it does. Might be nice to update it, but that money has to come from R-1 and P-1 and the JSF overruns have eaten all of that.
So the F-35 can and probably will be safe from termination, but nobody seriously imagines that the current, on-the-books plan - sustained deliveries of 120/year to the DoD - can be afforded at all. Anything close to that and there is no new bomber and other things go by the wayside as well. But significantly smaller quantities risk death-spiral territory - F-35Bs getting towards $200 m a pop in full production - unless some miracle-worker can achieve some major cost efficiencies, a task akin to redesigning and rebuilding a moving locomotive.
And read the tealeaves - it's not just Boeing doing new things to the Super Hornet, because the Navy is increasingly along for the ride.