Well, lets check the story:
DHS does not deny strong-arming tourist into letting them into his phone, only that agents sent him home because of a meme
www.independent.co.uk
So DHS said they did strong-arm him into searching his phone and stated they denied him for drug use.
However, that same article says this:
"A recent State Department cable directs diplomats to review social media profiles for “any indications of hostility towards the citizens, culture, government, institutions or founding principles of the United States.”
In recent months, reports of increased denials, detentions, and heightened scrutiny of visitors by DHS agents have made headlines.
In one instance,
a French researcher was denied entry after customs agents found a “personal opinion on the Trump administration's research policy” on his phone. The denial earned a public scolding by a French minister.
Last week, an Australian writer was
sent back to Melbourne after DHS agents in Los Angeles questioned him over his views on the Israeli treatment of Palestinians.
The general political tension and instability dovetailing with heightened security screenings have led several nations — including China, Denmark, and Finland — to issue travel warnings advising its citizens to consider if a trip to the United States is worth the risk of harassment or violence."
Seems like DHS has a pattern of denying entry to tourists who just so happen to disagree with the Trump administration. So my overall point is correct.