“As Russian and American forces have settled into Syria, analysts and experts have noticed a clear pattern from the Russian forces. Moscow is using Syria as both a test bed for its newest capabilities and as an opportunity to see American equipment such as the F-22 fighter jet up close. It’s a development that has raised concerns that Moscow may be gaining a military edge over the U.S. from its experiences in the region.”
Source: How the US has ‘learned a lot’ about Russian capabilities in Syria
