President Trump at the Group of Seven summit on June 9. (Cole Burston/Bloomberg)

Anne Applebaum, in her June 10 Sunday Opinion essay, “NATO is again practicing for the worst,” described a recent exercise to prepare NATO defense forces for the possibility of deterring a Russian invasion. Let’s connect the dots with the June 10 front-page article “In feud, Trump pulls U.S. from G-7 statement.”

President Trump’s action at the Group of Seven meeting is the latest move in a continuing and conscious effort to weaken NATO that began during the 2016 campaign and would provide the greatest benefit to Russian President Vladi­mir Putin. It is clear that Mr. Putin has an ally in the White House willing and able to weaken NATO.

The fair question is: What would cause the president of the United States to weaken ties with our strongest allies and seek the destruction of NATO? It seems entirely plausible that Russia possesses damaging information that, if made public, would be a major embarrassment to Mr. Trump, for example, the admission of collusion with the Trump campaign to sway the election. Or, perhaps, Mr. Trump is acting on a vague promise of something as mundane as a building permit for a Trump-­branded hotel in Moscow, something he has been seeking for decades.

Regardless, Mr. Trump seems willing to do Mr. Putin’s bidding. We know from history that for centuries Russia has had designs on overrunning Western Europe. It is clear that after all this waiting, Russia has finally found the means to its end.

Michael Goldfinger, Rockville

From his abhorrent behavior at the Group of Seven meeting, it is clear that President Trump is intent on destroying Western alliances as he daily usurps the pillars of our democracy. Meanwhile, the spineless, cowardly Republicans spout their usual platitudes as they fail to take action to remove or restrain him.

History will not be kind to the complicit Republicans who enable Mr. Trump in the subversion of democracy. Like Jacob Marley’s ghost dragging the chains, the Republicans will forever drag the Trump albatross down the corridors of history.

Carol Renza, Southbury, Conn.