The Russians are experts at jamming technology and possibly have “plasma stealth” technology.
The US is better at jamming technology (I’d also put parts of Europe ahead of Russia), and there’s no such thing as ‘plasma stealth’ outside Internet forums. While plasma state can cause RF not to effectively bounce back (hence the stealth), it is not a viable way of making aircraft stealthy as it exposes them to other forms of detection - hence it only existing in Internet fora.