How long until current 'stealth' techniques are compromised?

The detection systems alone do not render stealth aircraft useless...
but link it to the German anti-stealth seeking missile and it is an
effective counter.

But who needs missiles?
You dont even need exotic weapons like EM missiles,a multi static system
designed to detect stealth platforms might be turned into a "kill" system
instantly if you can keep frequencies and phases of several powerful emitters
under control,a kind of poor mans HPM weapon.