By John Shields
BBC US affairs analyst
For two days the Republican convention showcased the moderation, tolerance and optimism of the party.
Cheney stepped up the Republicans' attacks against Kerry
But for one night only, the knives came out at Madison Square Garden as the prime-time speakers poured scorn on presidential rival John Kerry.
In the keynote address, Georgia Democratic Senator Zell Miller, who has turned on his own party to back President George W Bush, denounced Kerry's "fainthearted self-indulgence", claiming the Massachusetts senator lacked the backbone to pursue the war on terror.
Vice-President Dick Cheney followed up with an attack on Mr Kerry's "habit of indecision".
Mr Cheney's dry demeanour contrasts sharply with the Hollywood glamour of California Governor Arnold Schwarzenegger, who raised the roof last night.
But he is a hero among the conservative party faithful, whose brightest stars have otherwise been kept under wraps in New York to woo swing voters.
Mr Cheney and Mr Miller are the only major speakers at the convention who have no presidential ambitions of their own, so they were able to turn nasty without fear of the consequences.
It is not clear whether the same can be said for the party as a whole.
Undecided voters tuning in on TV may have been turned off by the negativity of these attacks.
Firing up the base
Back in the convention hall, the delegates loved it.
Vice-President Cheney's quip that "Senator Kerry's liveliest disagreement is with himself" got a big laugh, while the more enthusiastic members of the audience brandished sandals, chanting "flip-flop, flip-flop".
Mr Kerry's respect for the United Nations was derided with loud boos, as was Senator Miller's claim that "Kerry would let Paris decide when America needs defending".
Miller's Democratic critics call him "Zig Zag Zell"
Short of firing up the party base, the impact of Mr Miller's attacks is likely to be limited.
His political acrobatics have earned him the nickname Zig Zag Zell among Georgia Democrats.
The speech marks the finale of his political career. He is not seeking re-election to the Senate in November.
Both message and messenger compare poorly with the keynote address at the Democratic convention - an appeal for national unity from the party's rising young African-American star Barack Obama.
Mr Cheney's impact beyond the convention hall is also limited.
He is the most powerful vice-president in history, but a recluse. His role as one of the main architects of the Iraq war makes him one of the most polarising figures in US politics.
He is the only speaker at this convention almost as popular as the president himself.
No speaker so far at this convention has outlined a convincing programme for a second Bush term, but they may not have to.
The polls suggest that attacks on Mr Kerry are working.
While anti-Kerry groups have questioned his military record, the Bush campaign has always said it respects his service.
But Wednesday night's speeches make it clear they have no such regard for his Senate career.
Listing Mr Kerry's votes against military spending, Mr Miller accused him of "selling off our national security".
We can expect plenty more of this kind of attack from the Bush campaign.
The Republican campaign message emerging from New York is potentially devastating in its simplicity: "We'll keep you safe, Kerry won't."