As I have said before, my crystal ball is broke and I can't tell the future of any tool company.
However, my short answer is yes and no. Yes, I feel Craftsman moving their sourcing of mechanics hand tools to China/Taiwan affected the lifespan of Armstrong tool factories. But it wasn't just Craftsman. The death of KD, Allen, US made NAPA, and other private labels like Kobalt and Masterforce also contributed to it. I also think the Sears pennies on the piece set pricing was also harmful to US made tools but, that's another thread.
For the second part of your question, I would say NO one can take over a US made tool line and make it competitive. Of course, you have to define the competition. Could a US made tool line compete against Harbor Freight? probably not price wise which is what most people tend to look at first. Your K Mart, Wal Mart shopper isn't going to save a US made tool line. Now competing between tool truck and non tool truck brands, possibly there's enough market share to carve out a niche.

In the end, there are still many US made tool options available. PROTO, Williams, SK, Blackhawk, Wright, all offer many US made tools. There are also more tools than you will ever use in the secondary market like Ebay too.
I wouldn't worry about which tool brand will be left standing years from now because no one knows. Just surround yourself with quality tools and you won't have any issues.