"Speak softly and carry a big stick" have been wise words for every president to heed since Vice President Teddy Roosevelt uttered his famous phrase for what is believed to be the first time at the 1901 Minnesota State Fair.

The U.S. still carries the big stick of military might. But President Donald Trump doesn't seem to get the speak softly part.

The latest evidence came late Sunday night when he intemperately tweeted: "To Iranian President Rouhani: NEVER, EVER THREATEN THE UNITED STATES AGAIN OR YOU WILL SUFFER CONSEQUENCES THE LIKES OF WHICH FEW THROUGHOUT HISTORY HAVE EVER SUFFERED BEFORE. WE ARE NO LONGER A COUNTRY THAT WILL STAND FOR YOUR DEMENTED WORDS OF VIOLENCE & DEATH. BE CAUTIOUS!" (And, yes, the capital letters were his doing.)

Caution is indeed advisable. For Hassan Rouhani, who seemingly provoked the president by telling Iranian diplomats that "America should know that peace with Iran is the mother of all peace and war with Iran is the mother of all wars." In other words, standard stuff from the theocracy, which has called our country the "great Satan" — an insult that likely offended previous presidents but did not lead any of them to issue the kind of dangerous threats that came from Trump on Sunday.

Trump rightly criticized former President Barack Obama for ignoring his chemical-weapons-use "red line" with Syrian President Bashar Assad. But Trump risks a similar paper-tiger growl by threatening extreme consequences because of empty rhetoric that is strikingly inconsistent with his campaign claims on the folly of going to war in Iraq and that comes amid his lack of focus on the enduring war in Afghanistan.

Focus is likely a key consideration here, too, as Trump turns to his familiar pattern of creating another alarming distraction to take the media spotlight from other news, such as the fiasco in Helsinki in which he appeared to side with an adversary that actually has attacked America — Russia. Every U.S. intelligence agency agrees that Russia intervened in the 2016 election and that it menaces the midterms this year, but Trump called that reality a "big hoax" in another unpresidential tweet sent on Sunday.

Or maybe he's trying to distract from his unsubstantial summit in Singapore with North Korean leader Kim Jong Un, who has made no demonstrable denuclearization moves since. What's more, Kim's government has subsequently accused the U.S. of "gangster-like" demands.

Congress, an equal branch of government, should not be distracted by Trump's diversionary tweets. Instead, leaders in both parties should remind the president of the congressional role in declaring war, reassure European allies alarmed by Trump treating Russia President Vladimir Putin more warmly than he did his counterparts at the NATO summit and protect the Mueller investigation that the president wrongly labels a "Witch Hunt."

After all, as Teddy Roosevelt stated: "Patriotism means to stand by the country. It does not mean to stand by the president, or any other public official, save exactly to the degree in which he himself stands by the country."