The enemy is at our gates. What is the president doing about it?

America is not known for traitors.

There were the Rosenbergs, Julius and Ethel. Put to death in 1953 for slipping nuclear weapon secrets to the Soviets. And Jonathan Pollard, with his long prison stint for a two-bit treachery that was more about aiding Israel than hurting the United States.

They’re historical trivia now. The only really famous betrayer of our country is that original American traitor, Benedict Arnold. Most Americans know the name, though could not, I would bet, offer up much regarding who Arnold was or what he did to earn his deathless disgrace.

Arnold was a hero in the Continental Army. In May 1775, he led a small party that seized Fort Ticonderoga from the British. He later invaded Canada, leading a march through Maine. The trek was famed for its hardship — his men were reduced to eating dogs and shoe leather. They attacked Quebec on New Year’s Eve 1775 but did not succeed.

A brave general. But by 1779, motivated by petty slights and a need for money, Arnold began communicating with the British. He accepted the command of West Point specifically because there he could “render the most essential service” to our enemy.

Arnold’s treason was twofold. Not only did he convey the design of the fort to the British, but in the summer of 1780, he neglected the defenses of West Point. He did not keep his troops in readiness because he planned to surrender the fort.

Maybe you see where I’m going with this. That second part of Arnold’s treason is relevant today.

Our current focus has been on whether Donald Trump and his campaign colluded with the Russians while seeking election. Courts of law will determine that someday. But there is a second aspect that might be even more important, one that needs no investigation: the neglect of America’s defense against foreign interference.

The first is, I suppose, open to sincere disagreement. As much as Trump is a consistent liar and obvious bully, I honestly do not know whether he engaged in active treason. He certainly acts like a guilty man, with his constant shrill attacks on the American intelligence agencies gathering information about how the Russians undermined Hillary Clinton while boosting Trump.

Two important events happened last week.

On Wednesday, the Senate Intelligence Committee, having heard testimony from the nation’s intelligence agencies, accepted their conclusion that the Russians interfered in the 2016 election and are still at it, trying to sway the 2018 mid-term elections. An info-war attack against our country.

“You can’t walk away from this and believe that Russia’s not currently active,” said Sen. Richard Burr, R-N.C., the committee’s chairman.

Then on Friday, Special Counsel Robert S. Mueller indicted 13 Russian nationals and three companies on criminal charges related to conspiracy to defraud the United States by undermining the 2016 election.

The president, who has been dismissing this attack on our country as a “hoax” and “fake news” for over a year, leapt to defend, not the country, but himself.

“Russia started their anti-US campaign in 2014, long before I announced that I would run for President,” he tweeted, dodging the point. (By 2013, Trump had already spent $1 million exploring a potential bid.) “The results of the election were not impacted. The Trump campaign did nothing wrong — no collusion!”

Maybe yes. Maybe no. More indictments will come, and we’ll see who among Trump’s inner circle, or Trump himself, is accused of illegal acts.

But right now, there is unarguable neglect if not betrayal going on in plain sight: Donald Trump has ignored — and is dismissing — a real, proven ongoing attack against this country. Instead of mobilizing forces to our nation’s aid, the president, like Benedict Arnold at West Point, has allowed our defenses to crumble.

When Arnold’s treason was uncovered, he fled. Those who trusted him were in shock. They did not make excuses, did not waffle. They accepted the obvious.

“Arnold has betrayed us!” George Washington said, fighting tears. “Whom can we trust now?”

We cannot trust the president, not because of what he may or may not have done in secret in the past, but because of what he is clearly doing or, rather, not doing, right now: defending our country against foreign enemies. We need to thwart a Russian attack on our system of government, and the president isn’t helping.