system
Given the following post, respond as if you're commenting on Reddit:
human
[Stargate] Would Ra really have stood a chance trying to take over Earth in the 90s?

If only by sheer numbers, we would swamp him, right? Let alone Spec Ops guerrilla warfare.

Edit:Even after the bomb would be increased a hundred fold, that wouldn’t take out most of the US because the bunker is underground.
gpt
Going by the Stargate SG-1 continuity, Ra would be more than capable of invading Earth again if he wanted to. The upgraded bomb would destroy the Stargate, cutting Earth off from its only avenue of escape or advanced technology, and then he could bring all the ships and forces needed to send Earth back to the stone age at his leisure.

During the early seasons of the show, two things protected Earth: its location (as the source of the slave population the Goa'uld used throughout the galaxy) was known only to a few of the oldest and most powerful of the System Lords, and those System Lords were spending most of their time fighting each other in the power vacuum left by Ra's death.

When Apophis did finally decide to deal with troublesome Earth, he took only two ships with him - and while the Goa'uld may be horribly outmatched by modern ground battlefield tactics, those two ships could easily destroy every major military installation and city on the planet with impunity, scattering humanity and turning us into easy pickings. Earth was only saved by SG-1 destroying both ships from the inside.

Ra only left Earth originally because the rebellious locals made the planet more trouble than it was worth. He'd already used humans to establish self-sufficient slave populations on hundreds of planets, and built an army that established his dominance over the other System Lords. There was simply no point sticking around on the otherwise out-of-the-way backwater planet.