The US is still very effective and well-trained compared to its peers, however the issue is armed forces all over the world (including the US, and other NATO countries, especially the UK and Germany) are in parts struggling with retention and providing training to their soliders/sailors/aircrew (flight-time to pilots in the case of Air force), so collectively standards are going down.

The Royal Air Force has less active fast jets (fighters and bombers) now than it had just bomber aircraft (Tornados) 20 years ago, and the Royal Navy is struggling to find sailors to man ships (not surprising given the pay, and the fact the UK doesn't do what the US armed forces do and pay for education, i.e. college).

If you look at accident reports over the past year from the US Air Force, the amount of flying time pilots are getting for practice every three months is around a third of what is was 10 years ago.