Essentially, the British – and later on the Israelis and the Americans – were/are totally dependent on air cover for their ground troops. NATO assumes that its soldiers will have air superiority on the battlefield. The Russians don’t make such an assumption and never have.
The Americans needed to test the air defenses of Syria before attacking it by manned aircraft – to be followed up by a ground invasion.
The drone attack was a total failure. The military of the USA have finally come to understand that they are second-rate on the battlefield. They no longer have air superiority. I expect there are a lot of frustrated people in Washington and Israel right now.