Tau'ri

Why did the Tau'ri avoid on trying to make their own Stargates or Spacegates or Supergates?

Obviously, most of the time Ha'taks only go up against iron-age rebellions, but when faced with air-to-air fighting with gliders or taking out large metropolitan areas like D.C in Stargate Continuum, the bombardment only really took out a maximum of like a block or so surrounding the impact zone of a bolt. Of course this would probably have been made up with the constant bombardment which would take place over many days and many lasers being fired, but even for a fleet of 30 Ha'taks like we see in Continuum, it would probably take a while for even one of the Tau'ri cities to get razed to the ground, and it would take probably a massive campaign for one or two ha'taks like Apophis's to go around destroying every city, giving someone on the ground enough time to invent a shield frequency disruptor and potentially take out the Ha'taks in their slow destruction across the countryside. It kind of reminds me of the V2 missiles used against London, where although the damage from the V2 wasnt as devestating as an all out bombing raid from the Germans, it still did a number on morale and was essentially impossible to stop them from attacking.