To finish the Louisiana Purchase, Jefferson needed to set aside the principles that he upheld. This is because the transaction that he was about to deal with were not states in the constitution. If he waited for amendments, the deal would have failed. However, he received full support from the Americans, and he went through with the purchase deal.
He therefore needed to take quick action since he realized that Spain had also signed a secret treaty to cede with France. This is the reason why the French government threatened America.
