I believe my Outback trailer came with Samsons. They're made in China. Lot's of negative comments on Chinese tires in the Outbackers forum. Had a blow out on one of mine in the first year. They lost air constantly. I upgraed to Maxxis. Went from a 14" load C to a 15" load D. Night and day difference. The Maxxis tires hold their air very well. After 20,000 miles they still look good.
I got a cheap set of Chain made TowMax on my 31' Jayco no issues.
It not the fact of china made it the fact most owners tend to drive faster than what the tire is rated for. Most all ST tires are rated for 65 MPH MAX. This doesn't mean drive right at 65 MPH and the tire should actually you right at the breaking point. So regardless of China made or not remember reduce your speeds and the tires will last much longer!
Speed is definitely an issue with trailer tires. One of the problems with my trailer is that the load range of my four tires was exactly the same as my loaded trailer. Each axel was rated at 3,500 lbs. The two tires on one axel had a load capacity of 3,500. The loaded weight of the trailer was 7,000. Two axles = 7,000. There simply was no margin of error. The Samson tires continuously lost air. So under inflation may have been a factor in the blowout.
I have that size as well. The 295/80R22.5 is one of the most expensive RV tires around. They are seldom used in the commercial trucking world, so priced as a specialty tire for large motorhomes. Take a look at Bridgestone, Hankook and Kumho brands. They are substantially less expensive than Michelin or Goodyear, but still top quality tires with excellent warranty and solid backing by a US distributor network.
You should also consider joining the FMCA if you are not already a member, so you can qualify for the FMCA Michelin Fleet Tire discount. That will bring the price of a top quality Michelin 295/80 down to something a bit less scary.