The first time we see that Tom Hagen is not a war time consigliere…
…is at the very beginning of the war.
Sollozzo surprises Tom, who, clearly alarmed, tries to hurry off but into Sollozzo’s muscle. “Make time, consigliere.”
And here there’s a pause, while Tom Hagen tries to absorb what’s happening. And Sollozzo, reading his thoughts, adds: “What are you worried about? If I wanted to kill you, you’d be dead already.”
A real consigliere, a war time consigliere, a Sicilian like Genco, would have already figured out that he was being summoned but was unlikely to be killed. And wouldn’t have shown a flicker of fear.
Tom Hagen was smart, capable and loyal, but just a half step too slow when things fell apart and it was about to get bloody.
And the Corleone’s enemies knew this. The sneer in Sollozzo’s voice when he calls Tom “consigliere” tells you everything about how he views him.