Roosevelt wasn't exactly a pacifist though. He took part in probably ever war ever fought in his lifetime (personally), was a big proponent of military parades/soldier glorification/heroism, denounced any attempts to make war appear tragic or bothersome, and was heavily campaigning for increased military funds all up until his death (rightfully so, as it would've made America better prepared for WW1).
https://en.wikipedia.org/wiki/Preparedness_Movement
"The notion that armaments led to war was turned on its head: refusal to arm in 1916 led Berlin to make war on the U.S. in 1917. The very weakness of American military power encouraged Berlin to start its unrestricted submarine attacks in 1917. It knew this meant war with America, but it could discount the immediate risk because the US Army was negligible and the new warships would not be at sea until 1919 by which time the war would be over, with Germany victorious.[16][17]"
When he talked about "speaking softly, but carrying a big stick", he was talking about making boasts that you cannot back up (which you could certainly criticize Trump for). Not that he was of the opinion that you shouldn't appear as strong as possible.
Trump, as a business man, knows the value of looking strong. But he does not necessarily understand that you shouldn't be trying to over-play your hand, and get caught bluffing.
