One Direction

Using their powers of camouflage, Malia Obama's Secret Service detail managed to go totally unnoticed at a tween-filled One Direction concert Thursday night ... well, ALMOST unnoticed.

While President Obama's 13-year-old daughter screamed her face off at the Patriot Center in Fairfax, VA ... one of her protectors kept his eyes peeled for danger while trying to blend in with the army of screaming teenage girls.

Things are all good between The Wanted and the boys from One Direction -- in fact, Nathan from The Wanted says he was even trading text messages with Liam from One Direction earlier in the day.

As TMZ first reported, the two boy bands had a run-in earlier this month when they were both booked in the same rehearsal space on the same day. We're told the boys from One Direction cut their rehearsal short because they didn't want to have a confrontation with The Wanted.

But last night in Hollywood, Nathan told us there is no reason for One Direction to be afraid of them. He told us, "I am pretty sure we don't intimate other teenage boys."

Watch til the end of the video if you want to hear a discussion about the going rate of used underwear.

The boy band One Direction was so concerned the other big boy band, The Wanted, was gonna beat on them, they tried to flee a Burbank studio ... but then The Wanted boys showed up.

Here's what we know ... On April 4, One Direction was rehearsing for SNL at CenterStaging, a Burbank rehearsal studio. Sources connected with CenterStaging tell us ... security for the band became aware that The Wanted was about to show up to rehearse for their "American Idol" performance the next day.

We're told the boys from One Direction -- all of them except Liam -- were scared because the British tabloids have been writing about tension and smack talk between the 2 bands. The One Direction lads talked about the guys from The Wanted being tough guys (which apparently is true) and they were worried about getting taunted and manhandled.

Our sources say One Direction decided to abruptly end the session and leave, but before that happened The Wanted showed up. The security team for The Wanted spoke with security for One Direction and discussed One Direction's fears. Security for The Wanted then told band members about One Direction's fears, and Max (from The Wanted) bolted into the studio where One Direction was wrapping up, laughed and gave Liam (he's from One Direction) a hug.

We're told everyone got a laugh out of it -- except Louis from One Direction, who wouldn't go near the boys from The Wanted.

Warning: Do not look directly at One Direction when the heartthrobs are shirtless and pounding beers Down Under -- that is unless you're prepared to lose your mind!!

British boy band One Direction is being sued by a much lesser known American band -- also called One Direction -- and now, the Americans are out for blood ... demanding the Brits change their name.

The U.S. One Direction just filed the lawsuit, claiming they formed in 2009 -- an entire year before the UK band members even knew each other -- and have since developed a considerable following this side of the Atlantic.

In addition to building a reputation around the name, the Americans claim they also beat the Brits in a race to the U.S. Patent and Trademark Office -- filing a trademark application for "One Direction" long before their UK counterparts.

Now, the Americans are asking for a court order -- requiring the Brits to change their name.

The Americans are also suing Simon Cowell's record label and Sony Music -- demanding more than $1 million in damages.

The British band -- which was formed by Simon Cowell in 2010 while members competed on the UK "X Factor" -- has yet to respond to the lawsuit.

In this new boy band era, The Wanted (top) -- Tom Parker, 23, Nathan Sykes, 18, Max George, 23, Siva Kaneswaran, 23, and Jay McGuiness, 21 -- and One Direction (bottom) -- Louis Tomlinson, 20, Niall Horan, 18, Liam Payne, 18, Zayn Malik, 19, and Harry Styles, 19 -- are vying for your crazed screaming tween's dollars.

Question is ...

There are five members in the hit British boy band One Direction -- and today in Dallas, there will be 20 security personnel for each of them ... to ensure their rabid fan base stays safe and in check.

According to our sources, a security team of 100 has been assigned to protect the group for their performance ... which is only supposed to last 45 minutes.

The band, which became the first UK group in history to debut at number one with their first album, is scheduled to play just four songs for a crowd of about 7,000 at the Dr Pepper Ballpark.

The security breaks down like this: 40 for close protection security, 50 more for the venue, and then 10 more just on stand by.