The US would impose a retaliatory tariff against another country if they were to attack US shipping during a time of war where the US was a neutral party or if the said country did something major violating a common right or disrespectful to the US as a whole and we would use the tariff to try to force them to fix the issue.
The missionaries in the Oregon Territory had a very different purpose than the rest of those in the area. Most people who went west and to the Oregon Terrritory were doing so to get land and start a farm. Missionaries, while they might have done this as well, were primarily there to spread the Christian Gospel and start Christian ministries such as churches and orphanages.
the smell of the air is the answer