Originally posted by viper37
Yes, they have a funny way of showing they love you 
But it's been argued before that it was perfectly legal according to maritime conventions of the time since the US was bringing supplies to the ennemy.
And someone here (or in the other thread about it) posted numbers showing that apparently there wasn't that much US sailors that were arrested, in fact many were Brits and other strangers that offered their services.
It was Britains own law (passed 1756) which allowed trade between neutral countries and powers at war. However, you're right, the convention dictated otherwise. Britain did seem to recognize that interfering with US trade was causing tension between the countries. In 1809 the British Minister in Washington (Erskine) negotiated to lift the blockade, but that was overturned by the British Foreign Secretary (Canning). In 1812, two days before the US Congress declared war, Britain agreed to end the interference, unfortunately Congress had no way of knowing this.
Many of the sailors impressed were, no doubt, foreign nationals serving on US ships. However that did give Britain the right to stop US ships on the high seas and kidnap sailors. Britain's pretence was that the sailors were deserters from the British Navy, which was certainly not true in many cases.
This is not to say that the British did not have good reason for what they did. They needed to stop Napoleon's ability to make war so they stopped US trade with the continent. They needed to man their ships to win the war, so they kidnapped US sailors. They needed to maintain good relations with their Iriquois allies to protect their own settlements, so they supplied gifts and munitions to them. They were aware, however, that these acts were aggravating the US and chose to continue them. To say that the British did not want war with the US, I think, is to absolve them of too much, as they certainly had the ability to prevent it, and chose not to. Nor would I say that the US is completely innocent either, we did want to annex Canada, and we wanted to restore our national honor, so we wanted war too.