The entire business with the raid:

[Toby]

k, This is how i see what happend.

1. You went armed to a Fumuku factory to hmm lets say "talk" to him
   
2. You were armed, You OBIOUSLY were ready to fight
   
3. You saw an Enemy, In THEIR base with a gun, PROTECTING himself and his facility
   
4. He doesnt let you in (OH i wonder why...)
   
5. You pull guns and start to crack his door, with raid calling IE Your raiding him, He retrieves his gun and protects his base... seems a legit reason to raid... (Sarcasm)
   
6. You kill him, and storm the place to find if there leader is there to hmm "Talk"
   
7. Hes not so you leave
   
8. Blackdog finds out
   
9. Obviously hes gonna be pissed off
   
10. Declares war on you
    

Please state Why you didn't try and solve this in a diplomatic way? (without fighting like "Badass's")

All in all..
You raided a base where you 'though' the leader was in an attempt to 'talk' to him..

Sounds more like you went to his base to 'abuse' him and get him to stop 'Fucking up your shit'..

Thats what i see of this whole thing..

Seems a legit reason..? No?