If all fighter jets become stealthy, how will they fight each other?

> LO remains relevant (and very useful) for the same reason armor didn't become obsolete when antitank guided missiles were fielded. [...] LO technologies drastically reduce detection ranges and warning times. Sensors that work well against stealthy aircraft would work far better against non-stealthy aircraft. What's the alternative to stealth? No stealth? Make our aircraft easier to detect and track? All future combat a/c designs must consider signature reduction going forward.

Can be seen as a commentary on isolation/mitigation techniques in infomation security.