@ep1 I am not saying this because I am an US citizen (I am a #SierraLeone ?? citizen too).
Still, the #UnitedStates ?? is strong enough to challenge #Russia ?? & #China ?? in a conventional war (no nukes or other weapons of mass destruction) at the same time.
This is due to technology & logistics, the latter which many countries struggle with on Earth (USA has mastered this).
Also the US has the most military alliances, so going to war with USA means fighting up to 50 other nations.