In the great classic martial advisory "The Art of War," Sun Tzu wrote:

Thus the expert in battle moves the enemy, and is not moved by him.

In a Fox News op-ed piece on Saturday, columnist David Marcus notes how the Trump campaign is doing just this, taking the fight to blue cities in blue states and forcing the Biden campaign to react to him, rather than the other way around. 

Former President Donald Trump is set to speak in North Philadelphia on Saturday, the next stop in what has been an unconventional but highly effective strategy of his 2024 presidential campaign.

It all started, as so many things in life do, with a trip to a bodega in New York City, and now it is a staple of the former president’s third run at the White House.

Back in April, at the beginning of a criminal trial that would limit his campaigning for weeks, Donald Trump showed up after court at a small locally owned store in Harlem for an impromptu and mostly organic little rally.

Within minutes, social media blew up with images of a diverse crowd chanting Trump’s name, with a kind of celebrity appeal we have not seen from a politician since at least Barack Obama. 

Next, Trump took his show to the Wildwood boardwalks of deep blue New Jersey, then to a rally in the Bronx, next to an event in a black church in Detroit, and on Saturday Trump will deliver remarks in North Philadelphia.

That's how it's done, and if the Trump campaign keeps this up, they will have the Biden people on their back feet throughout the campaign and should do well in November. In any conflict, some of the same rules apply as do in warfare:

1. Make your opponent react to you, not vice versa; don't put yourself in a position where your opponent can dictate the terms of the engagement.
2. Always leave your opponent a way to disengage. Don't drive them to desperation.
3. Know your opponent. Know his strengths as well as his weaknesses. Know his vulnerable points.
4. Strike where your opponent is weakest. Focus your efforts on that point.
5. Never make any statement or present any appearance that could be construed as weakness. Appear strong, even where you are not.
6. And, finally: Be gracious in victory. I know, the Biden administration and its minions have not done this, but there is an opportunity for Trump to be the better man.

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Here's the thing: This isn't something Joe Biden can do in reverse. The man himself has approval ratings that are down there with polecats and social diseases; he and members of his administration have been openly contemptuous of red-state folks and generally anyone to the political right of Vyacheslav Molotov. It's hard to imagine old Joe suddenly showing up in, say, West Virginia, Wyoming, Idaho, or, yes, Alaska's Susitna Valley and holding a rally; he would not be well-received, he does not know how to communicate with such an audience in any case, and honestly, he'd be wasting his time. 

Granted, the odds of Trump taking New York or New Jersey are infinitesimally small. But we have to wonder if that's his intent, although, per item five above, he is certainly talking as though he could win in those places. But what he is doing, Sun Tzu - or Carl Von Clausewitz - would have approved of, and that is keeping the Biden campaign unbalanced, off-kilter, and reacting rather than acting.

There's another Sun Tzu quote that is appropriate:

Let your plans be dark and impenetrable as night, and when you move, fall like a thunderbolt.

Consider that advice, and consider that the debates are coming up. Things are about to, as the saying goes, get real.