Originally posted by fullautoSherman:

i where them i would close it after the Russians tried to invade through the portal

Luckily, they wouldn't need to close it. The initial portal drop was one-way. The supposed invading Russians would then need to understand how the portal technology works and provide the portal sufficient power, both of which seem beyond the means of that time.

That said, I'm unclear how much this has to do with the game?

just a thought i had never got the game